Go white and light gray. +1 on it being cooler. I have had this rig for 3 years and even on the hotest days is bearable. Careful on the outside edges of the black seat…
Light grey gets just as dirty as dark, you can just see it more with the light grey. I am pretty anal about keeping my stuff in good shape so each spring I treat the carpet with scotchgard. Any stains wipe out easily with a wet towel. At the end of the year I run the wife’s steam cleaner on the carpets. And repeat the following year. Mine still look showroom.
As for cracking, not true at least on mine, and as for if do have to repair, solid gelcoat from doing something dumb, it will be much cheaper.