Keukenhof from Amsterdam - How to do it in 2 days after Viking River Cruise

don't underestimate the time your private driver will need to get through the traffic on either Thursday or Friday.

Both last year (twice) and once this year I drove my personal car to Keukenhof. The last 5km or so was bumper to bumper and very slow. Each time was perhaps half an hour in traffic.

Will your driver drop you off or are you using them as a mobile luggage locker on the way to your overnight hotel? Parking is expensive - in the vicinity of 20€.

Traffic getting out is heavy too.

I think your plan for all those extra stops is ambitious.

1) Is it better (less crowded, less traffic) to visit the Keukenhof gardens on a Thursday vs. a Friday?

It doesn’t really matter. That time of year the Keukenhof will be busy every day.

2) I’ve seen tours that include “skip the line” tickets to the garden. Are these legitimate? Or does “skip the line” just refer to tickets purchased in advance? If the former, will these be available on the Keukenhof website once tickets go on sale? How much more do these tickets cost vs. standard entry?

There is no such thing as special skip-the-line tours for the Keukenhof. The only line you could possibly be in, is the line for the ticket desk. Just buy your tickets online at the official website of the Keukenhof and your good to go.

3) I don’t imagine we will spend more than 3 hours or so at the gardens. Is there a city/town somewhat on the way back from Keukenhof to Amsterdam that is worth a stop? Haarlem? Leiden (not exactly on the way, but not too far from Lisse)? I’m guessing Delft will make for perhaps too long a day, but I'm open to suggestions if it's a must. Just thinking of a cute town for some shopping/drinks/take in the views. We love the water.

If you have a private driver, I would let him/her take you on a tour of the flower fields that surround the Keukenhof, rather than go to another city. Btw I think you’ll find that 3 hours is on the short side for a visit to the Keukenhof.

There will be express buses specifically designated from Amsterdam (and Leiden, and Haarlem, etc) to Keukenhof. They are easy to use and quite reasonable. After the first of the year, the Keukenhof site opens and sells "combi-tickets", that include entrance and the bus. I'm not sure a private driver is worth it- the driver will have to wait for you all day- and be charging you.
Do bring sandwiches and drinks- the food lines can get long.
And again, no such thing as "skip the line" tickets. I've never seen a line at the entrance that takes more than a minute.
It's a spectacular day, but tiring, so I wouldn't plan anything else . Just enjoy the magnificent gardens, with 7 million flowers bulbs!

When the website starts selling tickets, you will find tickets that include a timed entry, plus express bus tickets. That is about as close as you get to "skip the line"

Buses leave from Leiden, Haarlem, the airport, and the Amsterdam RAI station (you likely would need to take a tram metro, or bus to get there)

I would chose that rather than a private driver. The buses work well, and you can leave when you feel you have seen what you want.

Traffic from Amsterdam towards Rotterdam (A4 motorway) is generally lighter on a Friday for standard commuter traffic because a larger portion of the workforce works from home or takes a half-day. The morning traffic is way more bad the opposite direction. Regardless, try to plan your trip outside the rush hour, so post 9-9-30am and before 4pm).