What types of sink are you going with ... Vessel, drop in or undermount? What shape (round, oval, square, rectangular)?

I would suggest you make a sink template from cardboard (or rather two templates .. One for each sink) and see how they "feel" in the space ... Start with 18" wide and cut down if elbow room feels too tight in the space. At 18" you could have 2' between sinks with each sink 6" from walls on either side.

Also think about how the faucet is being installed ... Wall mount, counter mount or sink deck mount. This affects how deep the sink can be from front to back.

Thanks so much! The sinks are rectangular under mount with 8" faucets installed on the counter. I set up the templates. Both sink sizes seem fine (16 x 11 and 17 x 13). I would default to the smaller sink for more counter space. Since design is not my forte I am just not sure if the smaller sinks will look funny/puny given the vanity size (72").

Having the same issue, what did you use and how did it turn out?