First, I strongly agreed to jf813's suggested gear ratio.
if you want a bigger fan, you can try 40x40mm fan (I think your existing one is 25x25 or 30x30mm), and yes you can go to KWS, ask for a "fastest" once!!
Once I had a Novak 4.5 + SP ESC and the A,B,C motor gets really hot that they even melt the solder on the solder post. I emailed Novak and they said it could be the sensor unit on the motor failing. I tried another motor + same SP esc without problem.
So maybe you can try another motor, or change the sensor wire or just replace the TP sensor unit to do further testing.
進角, is on some of the motor, you can adjust the degree physically on the motor, normally have to un-do a few screws and turn to your choice of degree, and the effect is similar to Tubo on the ESC!