Normally:

I try to do the ballancing in the sanding off of the mold flashing (and sharp LE... TE can stay sharp because of how I hand-start) of the nylon/composite (Master Airscrew black, APC grey, Bolly Clubman) props. I rarely paint the tips of these.

I will first lightly sand the wood props on the front to get them close to proper balance, then I will dope the light lade face one coat, then coat the whole prop and re-balance. (repeat as needed) If I'm painting the tips for scale effect or increased visibility, I'll do it just before the clear coat. (sometimes double coating the light blade with the color.)

I always avoid alterign the rear of the blade, as changing that side slightly can create a dynamic imballance. (changes the AOA of the blade)