How feasible would it be to make the half bath a 3/4 instead (shower, no tub)? Then it can be an actual master suite and IMO, a lot more functional and also desirable in a rental. I tend to see a half bath more as the bathroom for guest usage, so it seems weird to me to stick the half bath inside a bed room.
For option 3, switching the half bath to full bath should be doable, at the cost of a smaller room.
Some thoughts on Option 2:
Expand the half bath into either a 3/4 or full bath, pushing into the current full bath.
Shrink bottom half of full bath, put toilet there. Move bath tub to top end of full bath, sink along the wall facing the window.
Other ideas, but may need changing windows
Turn half bath into laundry closet, stacked if necessary.
Turn full bath into bathroom for master suite. Increase width, reduce height.
Put another full bath on top of the master bathroom, grab space from current overly wide hallway.
Narrower hallway may need to jog to connect to back door.
Stick coat closet behind back door
On 2 vs 3 bedroom, it may depend on your area which has greater rental market. Having 3 bedrooms can work, I think, but I also believe you shouldn't force it if it'll make for an awkward layout.
edit to add:
Oh, and I totally admire what you're doing!