I’ve lived in South Florida since 1994 and I’ve never had a roach / ant problem in the rental. To be fair, I have had those tiny ants in my own apartment (which are easily sorted with gel) but I suspect that that’s us being lax with wiping up spills, poor storage and dry cat food which is open to the air all the time.
It depends on your situation. I agree that a microwave is a terrific addition to the room but are you able to check the room as soon as the guests move out? Luckily, I am and go into the rental before the guests even get to the end of the street to check for spills of food. That goes a long way towards sorting out the pest problem.
Also in the house manual, and during the house tour, I tell guests that leaving the doors or windows open will attract pests.
So, after all this ramble, yes I would add a microwave as an amenity if you can access your rental shortly after your guests check out. I’m sure that their appreciation will outweigh the potential bug problem.