With the leather belt since it's thicker ans softer compared to the standard belts, you just need to find that sweet spot (the right angle with the right amount of pressure).

I don't really keep count of how often I reapply the compound. I can feel the difference with the edge when the compound is worn out, and when I feel it's not abrasive enough, I apply more.

I keep the side cover off my delta as well, i try to vacuum as much dust as possible from all the moving parts to keep everything running smoother, but I haven't had to do any maintenance except tightening the drive belt. See if that helps transition the the power more smoothly, because the belt does get more slack from when you first assemble it.