I think I (the OP)
have now determined it, for myself anyway: A
Kubota Grand L3940 HST w/ QA LA724 FEL, QA bucket, & R4 tires.
Seems it'll fulfill my "needs"

& wants better than the others I've looked at & researched.
Drove one recently & these things are pretty slick:
- Auto throttle. Lets the engine drop to idle when your foot's not pushing the HST pedal.
- Ability to actually drive/ accelerate with only the cruise control level on the left.
Of course, you can turn all the bells & whistles off & drive it like a "regular" ol' tractor (with plain jane HST, that is) if you want.