The endbell timing is tricky, partly because not all motors are labeled the same. For example, and if memory serves, early Novak Ballistics had 30° of timing when the label was at zero. Later ones were labeled with the 30° as the starting point. Some other brands start in the 10 to 20° range if I'm not mistaken.

But in general some timing is needed, I would not start with 0 endbell. I'd start with whatever the motor came with. Maybe a little lower if you know it's a 30° motor.

Then gear down, as boost done right can add a lot of RPM. I had good luck with gearing a good 20-25% or more lower than blinky. Then add in boost carefully. Get it right and a boost setup can be fast and run fairly cool, as proper boost ramping keeps the motor in a more efficient range. But be careful, it also can go over the edge very quickly when overdone. Lots of quick temp checks when testing.