Mostly, your going to get two schools of thought here.
Thought number one is to run lighter bullets and reduce your recoil and or run lighter bullets with a reduced powder charge and reduce your recoil (fillers needed)
Thought number two is to run a full case of powder and big heavy bullets. "Shoot it like our forefathers did!!" Forgetting to mention our forefathers probably only shot 20 rounds in the entire time they had the gun.
Thought number Three is .... Oh crap, I forgot there were three schools of thought. Third school of thought is reduce the size of the cartridge case, which reduces the amount of powder and then include a lighter bullet. All of which reduces recoil and no fillers.
The smaller case also helps out when you running light loads of that heathen fad smokeless stuff. Better ignition.
I personally shoot APP .... a substitute. Loads just like real BP, makes a bit more smoke and NO lubes are required. Makes it's own lube. Which means I can shoot any bullet, any lube or no lube, doesn't matter. I'm a card carrying, dyed in the wool recoil WIMP. No ifs, ands or Butts. I do not like recoil. Therefore I personally run Cowboy 45 Special cases, 2f APP and 160Gr bullets. Quite pleasant to shoot.
Coffinmaker
PS: Regardless of powder, bullet or case configuration, the 45 likes a nice tight roll crimp.