Here in Texas, heat tolerance is a big issue. Most rabbit breeds don't do well after the temperature reaches 80 degrees. Since our summers routinely hit over 100 degrees, here are a few things to look for while searching for a heat tolerant rabbit. Tamuks in particular were specifically bred for heat tolerance.
look for BIG EARS
Rabbits' ears cool them by cooling the blood as it flows through them.
Look for ears that have very little hair on them
look for BIG FEET
The only place rabbits can sweat is their feet. So big feet help keep them cooler
If you want to breed your rabbit for meat, look for GOOD SHAPE
Look for a nice arch to their back - the back and hips are where most of the meat will be. The pictures are the same rabbit at 7 weeks and 11 weeks. I really need to get better pictures, but it's late and I'm tired.
Also look from above.
You want a nice fat teardrop shape. These kits are about 7 weeks old.