I would probably go back to Hokkaido in winter / early spring. But rent a 4x4 and just travel around wherever I feel like. If somewhere I haven’t already been, then maybe a coast-to-coast road trip across Canada.
New skill - honestly, anything creative. All my interests (aside from walking) are very passive. Any kind of ‘doing’ talent would be awesome, like writing or making clothes so on so on.
Improve skill - Japanese / Korean (could quite easily do this but I’m really lazy)