First time in Greece- ten days

There are definitely other options, but you may have definite reasons for choosing what you want to see and do, and where to go.

Our first Greece trip, for 2 weeks, started when we landed in Athens at night, then headed to the Island Hydra the next morning, for two nights. We then got back to mainland Greece (ferry to Ermioni), where we picked up a rental car (from Pop’s Car Rental) and drove to Nafplio for 2 nights, driving to several ancient sites.

The next week was spent on the Peloponnese Peninsula, visiting many additional historic places, and staying in Monemvasia, Areopoli, Kalamata, and Olympia. We visited Archaea Olympia, the stadium and temples where the original Olympic Games were held thousands of years ago, plus a fantastic museum.

We next drove north, crossed a bridge that’s almost 2 miles across, and stayed in Delphi for one night. We’d planned to stay for 2 nights, but the city was so noisy that we packed up and got another, better room for a night in a much nicer town, Galaxidi. Next, we drove to Athens, turned in the car, and stayed for 3 nights. This was in April, and we were there to see ancient sights, and not beaches.

Our second trip, starting in September the following year, was only Crete, but also for two weeks. We did get a couple of days at one black-sand beach, at Kato Zakros, along with many historic places in the interior, plus the two biggest cities on the north coast, Iraklio (aka Heraklion) and Hania (aka Chania). Crete for just 4-5 nights would give you a tiny peek at the big island, maybe staying in just the two biggest cities and moving on. I would suggest taking a week or more, just for Crete. If you were island hopping, Crete could be one of the islands, although I’d imagine you’d be flying there and back, not going by ferry, if you were squeezing Crete within a 10-day trip.

I haven’t been to Santorini, Paros, or Naxos yet, and one day, I’d like to see Delos, and take cooking lessons on Ikaria.

There are dozens (if not hundreds) of other options. "Better" doesn’t exist, it’s really about having experienced a few options yourself, and after that it's purely a matter of personal preference.

What your friends recommended might work for you... or it might not. What Cyn experienced might work for you, or it might not. Either way, it's true that less than a week in Crete isn't necessarily worth it.

One of the basic rules is to keep in mind that getting around in Greece practically takes a lot more time than flipping pages in a guidebook, and that in the islands, ferries don't run from just any island to any other.

I would also add our own personal golden rule: We don't go places that don't personally interest us, even if they're recommended by friends, and especially not places that are hyped up on Instagram or other social media. The more buzz there is about a place, the twice as hard you should think before going.

How many full days will you have on the ground?

If it is 10, travel from Athens to the next place will take one day, then travel from the next place back to Athens for the flight home will take another day. That leaves you eight days to sightsee. If you add in another destination, you lose another day.
And note what JoLui says about how ferries run.
If it were me I'd choose one other place than Athens that you want to see, and split your time.

I am not sure where you are coming from, but if you are flying from North America Many experienced travellers get out to their first island destination on day of arrival in Greece. Many of us leave Athens to the end of the trip. Athens can be overwhelming particularly when jet lagged.

Every island hop you make will take up about half a day so your plan to island hop is going to eat up a lot of time on ferries.
Less is more when travelling in Greece.
Crete actually needs about 2 weeks as a minimum.
You might want to consider getting to your first island on day of arrival in Athens. Fly or ferry to that island.

Both Naxos and Paros are good destinations and you can easily spend a week on either and not see everything they have to offer.
Just choose one island and take the time to explore. While Santorini is a good destination it is expensive and very busy. There are excursion boats from both Naxos and Paros that you can take to visit Santorini so you can get the experience without having to pay the high cost of staying in Santorini.

What’s missing from your question is what you want to do and what you are interested in—why did you choose Greece? I’d rather get personalized feedback than find out what worked for random other people!

Stanbr gave you good advice. I’d pick either Paros or Naxos, depending on lodging & flight availability, and fly to that island immediately after landing in Athens (give yourself 2 hours connection time).

Both islands offer day trips to other islands, so there’s no need to change locations/hotels to get a variety of experiences. Fly or ferry back to Athens and explore the city afterwards for a few days.

When making your plans, think in terms of how many nights you have. 10 days means 9 nights, so spending 6 nights on the island gives you 5 full days. If one day is a daytrip to Mykonos or Santorini, that gives you just 4 days on the island. And would leave 3 nights (2 full days) for Athens.

Thank you everyone for your prompt replies. Based on the responses, it's clear "Less is More". So Crete is out.
And trying to decide on the second main destination other than Athens- Naxos, Paros or Sifnos or perhaps Hydra even. They all sound SO good. (I know Hydra is not on the same route as the others. ) Santorini is still in the mix, but willing to let it go- since it seems over touristed- breathtaking beautiful but seems to be very commercial.
We are not lounge on the beach type of people on Europe trips because we get our beach fill when we go to Hawaii. We prefer walking around, soaking in the vibe, culture, history, food, music and lively evenings.

Any recommendations please?

In my opinion, the only place that checks all the boxes for you is Sifnos.

No crowds (or at least way fewer than Paros and Naxos), and no need to hang out on or near the most overcrowded beaches, though there are some gorgeous ones that are nothing like Hawaii. It's a true postcard of a typical Cycladic island, one of the best islands for hiking. And for you, the icing on the cake since Sifnos is famous for its food, it will host just like every year in September the Nikolaos Tselemedes Cycladic Gastronomy Festival . This year it's happening on September 17, 18, and 19. When it comes to "food, music, and lively evenings" you literally can't beat it with any other island.

https://sifnos.e-sifnos.com/what-to-do-in-sifnos/cooking-festival-in-sifnos.php

However, there's no airport on Sifnos, so you'll need to spend a night in Piraeus to catch a ferry the next morning, and try not to get tempted like so many people by a flight to Naxos or Paros.

Leaving Piraeus at 9:00 AM, you'll be in Sifnos by 11:30 AM.

To find accommodation as well as things to do and see:

https://sifnos.e-sifnos.com/index.php

A few photos:

https://photos.app.goo.gl/9tHZVYU8tLRyfkND7

Now I'll hand it over to the Naxos superfans to see what they actually have to offer : -)

Agree with @JoLui. Take a look at Sifnos.

Our first trip to Greece went like this:

Arrive Athens, drive directly to Delphi for the night;

Visit the Delphi historical sites and museum, then drive to Meteora;

Two nights to explore Meteora which was awesome;

Return to Piraeus and ferry to Sifnos;

Several days on Sifnos then ferry to Milos (would not return) for a few days;

Return to Athens to explore before departing.

We have returned to Greece several times since. Our favorites are still Meteora and Sifnos.

Wishing you a great trip!

Thanks @JoLui and @mml. The Sifnos food festival sounds fun. Any recommendations on where to stay, considering things will likely be already booked and pretty $$.

Regarding accommodation, I already gave you this link in your other thread (Sifnos Greece):

https://www.roomsinsifnos.com/

We’ve stayed in several places on Sifnos, we’ve visited 4 times (or 5? I’ve lost count) since the 90'.

Generally, giving specific recommendations is pointless without knowing what people are looking for, but just in case, the last 2 times, we stayed at these places:

In Kastro (a car is essential):

https://arismaria-traditional.com/en/

In Faros:

https://sifnos.e-sifnos.com/diaf/sifnos-hotels-rooms/faros/giannas-apartments/gianna-apartmens.php

I believe Janet, who posts here, knows a good place in Apollonia.

I wouldn't recommend staying at the port of Kamares, in my opinion it's a bit too far out of the way for exploring the island (though not to the point of being a deal-breaker).

You make a good case, JoLui, but Sifnos does not allow day trips to Mykonos/Delos or Santorini — or to Antiparos (from Paros).

And with such a short trip, spending overnight in Piraeus seems to “waste” a day (although I know not everyone agrees on this).

I love Sifnos too but for a very short first trip … up to the OP to decide.

Charlene, it’s true that getting to Delos or Santorini from Sifnos isn't easy, it’s a matter of choice. It’s like going to Florence and regretting that you can’t visit the Vatican, or visiting the French Riviera and missing out on the Eiffel Tower. From what I’ve read, Manisha hasn’t mentioned wanting to go to Delos and doesn’t seem very keen on Santorini.

So, it’s up to them to decide.

As for spending the night in Piraeus, I don’t think it’s a waste of time at all, it’s an integral part of the trip. I’ve always loved Piraeus and it’s far more than just a port. In fact, Piraeus is just as much a day-trip destination as Delos or Santorini (albeit of a different kind).
Plus, the OP has 10 days, which is perfect for visiting an island and spending a few days in Athens.

But as I said, one can always take the easy route, I don’t mind, it’s not my vacation after all. I'm not at all opposed to going to Paros, Antiparos, Naxos, or anywhere else, even Santorini! . I have visited all these islands, each has its pros and cons, I’m just making suggestions.