Flight Detent: On the 737 there are temperature indicators even on the classics, not to mention the Ng's. On the Ng you'll find brake temp indicator mostly on the -800 CDS ,on the rest is not required.
The difference is in the brake assembly design, the ones on the 737 allow for a very good cooling. No fan required or ever installed on a 737.
You may land at full weight with a 737-700 on a short rwy,brake 3 ,and you'll have no cooling time required in the brake cooling schedule.
The brakes on the classics are a bit less efective, but never had a problem with them.