One sink would be fine but I want to keep my bathtub.
Doesn't look like you have room from what I can see of the sideways picture. Is there another area?
Great ideas - thank you!
Your best bet looks to be the cabinets behind the tub. If your plumbing is on the shared wall it could also save you money to do it there as the plumbing could be shared to the shower and the tub.