or possibly the nearest unoccupied seat

Mainly I was thinking about this for PCR, where there will be kerbals in the other chairs. But maybe it's more reasonable to just swap to that kerbal and have your current one go back to their seat?

proposed design:
[y] swap sweats with <name>
[v] switch to <name>

That way, Y is always "enter seat" and V is always "switch kerbals"

Swapping is a bit harder, so I'll just do "switch to" for now