Hi doc!

First of all, early congratulations on your retirement! I'm surprised you have only a few countries planned for Europe. How about going further central or east Europe or down south?
- Austria, Czech Republic (Prague), Turkey... I heard they're beautiful
- Italy, I heard from colleagues they really hate speaking English but food is good.

Next about your Japan trip: I'm going for cherry blossom this year and we're making a (hopefully) decent itinerary not sure how it'll turn out yet but we're planning for a lot of pretty pinks (hanami/flower viewing) lol. I would highly recommend a long stay as we've already packed our 2 weeks full just within Kansai. Previously went Fujisan, Hakone and a few more places during the winter, I really enjoyed onsen in that painfully cold weather. You'll probably enjoy ryokan stays with private onsen based on your budget lol.

Lastly, I'm developing an itinerary planner on Google spreadsheet which I think will work well if you have a list of places you want to go and you want to optimise the route between these places, and the time taken in between. Here's a sneak peek on phone (it's not meant for usage on phone because it's intended to be a pre and post trip planner, but view only for day of execution... but I'm writing this on phone so....)

If you're interested, feel free to PM me
Grey text is all formulas/auto-calculated and how I get the values are based on Google map's direction with limited configuration... It's good enough as an estimator.

Personally to me, trips are tiring AF indeed because wanna go as much places as possible given limited time and money, but I think for TS, the whole point is to enjoy his retirement slowly - time and money are not the constraints but energy is (old age.. no offense uncle), so it's all the more important to plan the itinerary well.

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I extended business trip to go on a short personal trip with a colleague to Belgium. The places were like +/-1km apart all the way, so we ended up walking a total of 12km in a day, which is a crazy feat for sedentary IT people like us lmao. So yeah, even though I planned all the route so optimised they're close to each other, problem was that I did not consider our energy levels - in hindsight I really loved it anyway because we managed it and had a lot of fun, but we were complaining to each other KAKI PATAH as we walked.

P.S. I kasi Google my location at all times, so I get to enjoy a timeline of my trip and the distance + places covered. This can be a fun thing if you don't mind giving away your privacy to Google (note that they're all private information by default anyway).