I've got both. I'm hunting snowshoe hare rather than squirrels these days, but I've used the 36 only once since buying the 32. Just suits me better somehow. No shade on the 36. I think my 32 balances better for offhand shooting, but that's a detail of the rifle rather than the bore.
As for fouling, that's a tempest in a teapot in my experience. With a reasonably tight patch and ball combo to help "scrub" the fouling each time I seat a new load, it's just not an issue. I've never pushed either one past 20 rounds without swabbing, but that's cuzz I've only shot 20 rounds in a session. And "tight enough" doesn't require a hammer either.... just firm pressure on the short starter. It helps to use a patch lube that softens the fouling though. Liquids usually work better than greases for that, ranging from spit to Hoppes #9+, and even Windex, if I recall correctly. Only know about the spit and Hoppes, but it sure works with them.
For loads, I hold things down to around 22 LR velocities. That .310 or .350 ball at 22 LR velocities is plenty to ruin a whole lot of meat if you wander back from the head. In the 32 that translates into 15 grains of 3f Goex or Pyrodex P, and in the 36 it's 20 grains of the same powders. Lots of folks use more, but heck, I can't see well enough for head shooting much past 30-35 yards. And both guns will pop heads a lot further if you can see them.