This question of what would I buy, comes up from time to time on pilot forums and my list doesn't change much over the years, although I think this year I'll add a helicopter just because it would be fun to learn to fly it.
1- Rebuild my M20F to be as close to a M20K as I can, just because I can.
2- Lancair Legacy, but this year I'll add a ballistic parachute system.
3- Leza Air Cam on floats
4- Socota TBM-850
5- Focke Wulf 190a
6- Robinson R-22
Since I would be retired, I might actually try building the Air Cam myself and if it goes well and I like it, I might do the Legacy myself too.
[edit] Oh, and because the Air Cam and Focke Wulf would require me to get a tailwheel endorsement, sea plane rating and a multi rating, I would probably buy for training purposes-
1- Aviat Husky A-1C, Get tail wheel, then put it on floats.
2- Grumman Cougar just because it's different.
If it turns out in the end that I really like STOL tail wheel/bush flying, I would then trade the Husky for a Fieseler Fi-156 Storch.