OP, as someone that has owned everything from black to tan to grey to ecru (off-white, in a convertible of all things) leather seats, I would NEVER consider putting lighter color leather in a car I was going to rent out unless you are prepared for some maintenance. I personally don't consider upkeep of lighter color leather seats to be a problem for me -- but I also don't have a bunch of people that frankly won't care the same way jumping in and out of the seats, never to be seen again. IMHO for your "business model", I'd go with black seats, no matter what your personal esthetics may prefer.
FWIW I have grey next gen seats in my 3-week old MS, and while I am happy with my choice, already know my preventative and ongoing maintenance will be necessary with my Tesla -- no different than the (perhaps even more supple) grey leather seats I had in one of my former Lexus for nearly 8 years. That leather looked great when I sold it, with only natural age wrinkles, but I also was diligent about upkeep, and learned to keep my rump from rubbing as much on the lower side bolster which also helped reduce some dye transfer and wear.