6 Week Itinerary from New Zealand - Help plz

Just as an aide in planning, it is usually helpful to count nights in a location, not days. Due to travel time between places taking 1/2 to most of a day, 2 nights in a place means 1 full day there, plus a half day on arrival or departure day. Also, in laying out your route, I would first check out the best ways to go from place to place (air, train, bus, ferry). Knowing the range and cost of your transfer options helps in planning.
Overall, your must-see cities are ones I would choose also. There is a reason London, Paris and Rome are the top cities to visit. And going in Europe's winter season will cut down on the crowds you would encounter in the summer. (I confess to having a special place in my memories for Vienna.) Have a wonderful trip to Europe!

I love Greece and have been there three times with another trip planned next year. But it is out of the way and wonder if you would not be better off using the nights elsewhere. I have been to Crete and spent 11 nights which was not enough so the idea of going to all the trouble of flying there for three nights in off season especially seems to be worth reconsidering.

I know you are in your 30s but even when I was I would have found the pace you are proposing too much to keep up for 40 days. At the very least I would add an extra day for laundry and not doing too much in the middle of your trip.

I think starting with London is a good idea but would add another day since the day you arrive will not be a real day. We spent 5 nights in London our first time and found that to be a good amount of time. But we moved on to Bath, England not Paris but only you know how much you would enjoy one urban destination after another. I would consider adding more smaller destinations to complement the blockbuster cities.

I would choose Option 1, allowing you to acclimate in an English-speaking environment. For reference, I was 69 when I first went to Europe and don't find your pace too fast--you might, but I'm just saying you won't know until you try. I've spent over 100 nights on the continent now and still would go this fast in my 70's.

I second the notion of adding a night to London at the beginning because there will surely be some exhaustion and/or jet lag leftover from the trip. Just consider the first night a time to crash. Whatever your first destination is, add 1 night for getting yourselves together. As for Greece, you decide (I haven't been there yet, but very much look forward to it). Based solely on what I read, Crete seems like too much travel chaos for what you would get out of a short visit, so personally I'd reassign those three nights.

For additions, consider Berlin. It's not typical Germany and isn't especially charming, but it would introduce you to the country and is extremely interesting. It also has a young energy that's very attractive and that you would no doubt enjoy. (If you did this, it would mean flying from Athens to Berlin, then on down to Prague (also Germanic but quite different) and Vienna, a great final stop. If you don't want to do Berlin, or want to squeeze in even more with your extra 5 nights, give some real thought to Spain. Madrid is a modern city, also quite hip in some spots, with an assortment of interesting day trips possible. Barcelona is a different vibe altogether and Mediterranean in spirit with unique architecture. The down side of Spain is that this would require another plane trip from anywhere on your current itinerary.

Lastly, regarding the comments about mixing in some smaller places: for a first trip, and a fast-paced one at that, I would keep your lodging in major cities near transportation and then if and when you are tired of that, there are day trips you can take either on your own or with a tour group out into the countryside or at least smaller cities.

Good advice above about starting to figure out the transportation and letting that govern some of your planning. Also start tracking what you actually would want to do in or from each city, and guesstimate how much time each will take. When you don't know, you can ask on this forum, under the appropriate country.

I agree that Greece/Crete are kind of outliers, and would save them for another trip (I had my first Europe trip at the age of 30, for four months, luckily! and still didn't get to Spain, Hungary Greece or Scandinavia). Putting in some no plan/do nothing days 2 or 3 times will rejuvenate you and give you a chance for laundry and just goofing off. I would take your Crete and Athens nights from option one and add 2 each to London, Paris and Rome. You can do a day trip or overnighter from each city (London...Bath, Windsor, Oxford, Stonehenge; Paris....Reims, Chartres, Lyon, Beaune; Rome....Naples/Pompeii, Ostia Antica, Villa d'Este, Sorrento) Lots of choices for day trips or overnights from the big three, plus you cut out a couple of long travel days.

As an aside, I understand the departure tax from London is quite a bit higher than from other cities, so flying into London and leaving from Vienna seems to be the better option. Best of luck and have fun with your planning and with the tripo!

CHOOSE OPTION 1
You are in your 30's and are travelling westwards. This means you've got everything going for you and will have no time zone fatigue, quite the opposite. You have put in some sterling work planning this journey, and the layout is so good it has to be assumed that handling words and images is your occupation. Here's some advice:

GENERAL
Travel north to south to make the most of the available daylight, which is decreasing noticeably in the north at that time of year. Arriving in London NOV 15 i better than arriving DEC 15. You will likely be overwhelmed by Christmas decorations everywhere anyway as consumerism is on the increase. Rome was lovely in January as the light doesn't ever change that much down south. I was preparing to recommend Greece, but you have already included two Greek destinations. Don’t desert them. 11 hotels can be counted. Consider always staying at least 3 nights as changing hotels is a hassle and eats up time.

London / Paris
This city is unbounded. 1-2 nights could be added when you’ve come all this way to experience the jewel in the crown of this former, quite short-lived, empire. See a play. Walk Hyde Park in the darkened Victorian evening, autumn leaves falling in the mist, feeling as though you are in Elephant Man (1980) or Dracula (1992). Don’t add nights to Paris unless you are Parisophiles. Malmaison, d’Orsay, Fontainebleau.

Strasbourg / Zermatt / Zürich
Add one night to Strasbourg. Zürich (pop. 400 000) is a good choice for another Swiss city. Chocolate, nice old buildings, trams and a lake.

Florence / Rome
This is the one destination on your list that should be studied scrupulously, with an industrial strength magnifying glass. Read reviews, trip reports and replies in the forum to divine if Florence is a travellers haven or overrun, stampeded and prone to putting you In the Mouth of Madness (1994). Let me go against the grain here and contradict the probable replies of each and every NA or UK responder and suggest that you abstain. The David sculpture is overrated as his mentor, Donatello, is the superior artist. My recommendation otherwise, is to stay 3 nights in lovely walled Lucca and day trip to Florence one day and to Pisa the next day. They are minutes away by train. I would concentrate on the Bargello, see one of the open air Davids and then have gelato.
Rome has more museums than anyone could ever wish for, and you could add 1-2 nights (or a whole year) as Rome is eternal and unending. Be wary of the Vatican/Sistine places, where you are as cattle to be herded through a pen, and read their reviews carefully. Beware the mouth of madness. If you need calm consider a day trip to Ostia Antica or Viterbo.

Athens / Crete
As this is a once in a lifetime trip you must, by all means, experience Greece, which the Roman Empire spent the entirety of its existence trying to emulate. Crete gets the last of the remaining heat. I have swum from its beaches in October. Stay in Chania or Rethymno. The Palace of Knossos is interesting but optional.
Athens is a capital that, in contrast to all other capitals, holds only a fraction of the amount of museums and temples that should be found there. Acropolis, one more temple and 1-3 museums, when you are the jewel in the crown of the entire ancient world, beholden only to Egypt, is hardly even a beginning. Go there, see the sights, and day trip to Epidauros and/or Delphi. Prepare yourself for the ancient languorous ambience of Hellas by watching Picnic at Hanging Rock (1975). Let the sun blind you and the waves speak to you, like they have done since time immemorial.

Prague / Vienna
Three nights in Prague is all you need, as it is circumscribed and not that exciting. I went to a small suburb in the wooded hills for the evening. Choosing Vienna for your last stop is a fortunate and rewarding decision. Wunderbar!

traveller,
You are getting lots of advice, and on this forum there will be lots of contradictions and strong opinions. Trust your own instincts, choose your own places, listen to the practical type of suggestions, but make this trip your own, going to and seeing what draws you. There is no MUST! Continue to winnow out the things that are less important to you so you can enjoy those that are more important and have some down time. (I guess "some down time" is kind of a good idea, maybe a must in lower case letters.) What is that kids' game? "Choose your own adventure"!

Anyway, you will have a great time, and make some wonderful memories!

For planning European train travel you really can’t beat the advice given by The Man in Seat 61. Here’s his website. seat61.com

He not only has detailed information on timetables and route including best use of sleeper trains but also how to buy the tickets to get best price etc. An amazing resource.