Those look very nice indeed, Stephen, and the freehand numbers on the cartridge pouches look great! I sympathise entirely with the challenge of head-swapping for shakos, but I couldn't stand to have them all wearing shapkas either.
Hi Sergio. For 28mm figures I use flag poles of 60mm length for infantry, and 50mm for cavalry. Length does not include the 'finial' (ornament) on top of the poles. Use what seems to look best for your figures.