I may be out of line here and not understanding something but, I thought gearing was as tall as it gets at 1:1. Once you start going, in your case, 36/35, doesn't that start lowering the gearing?

Whats the difference in having a 60t spur and 20t pinion or a 20t spur and a 60t pinion. Won't the vehicle go the same speed?

As for your motor selection, you can find Leopard 92mm cans with almost 1800kv. I don't think they are made new anymore but when I was looking for my 1492kv 4092 motor I saw a couple. I can't however tell you whether they can handle 8s however, I have had great luck and moderate experience over volting motors with no ill effect.... except on a 15t brushed motor.