And you won't see any at the level you are loading. Depending on the revolver (in my case it's either going to be Blackhawk's or FA83's) you won't see any "classic" signs of pressure until you are way past any comfort level. In my 44 Magnum FA83, I probably would never see any pressure issue even with a case full of bullseye and a 300 grain bullet. Pick a load that meets your goals and work with it safely. What I mean is pick a bullet weight, pick a velocity, and work with that accurately. A S&W 29 will be a different critter than a stronger SA revolver but can handle medium loads (240 grain bullets and 1000-1100 fps) probably indefinitely.
I don't use lightweight bullets (with one exception in 44 Special) and I don't load pipsqueak loads. I find accuracy in the 44/45's using a standard or heavier bullet (240 + for 44's and 250 + for 45's) in the medium velocity range and hotter. I understand folk want to use what they have but the bigger capacity cases work very well with medium and slower powders (HS-6 would be my medium example and AA9/2400 would be my slower example). The examples of slower powders I just used can be played with as they don't hate to be downloaded. When you get to H110/296 range, they are meant to be rock crushing loads and can be interesting. I can be completely happy only using HS-6, AA9, and H110 for all of my revolver needs.
As others have mentioned, I only use Magnum cases in a Magnum chamber. My 44 Special cases only go in my 44 Special revolvers (same for 357/38 Spec, 327 Federal/32 H&R). Everybody does their own thing and that's perfectly fine but keep in mind a 44 Magnum case loaded with a medium burn rate powder will act just like a 44 Special case loaded with a fast burn rate powder and do it at a lower pressure and maybe better accuracy. The 44 Magnum case will also not leave fouling some place in the cylinder you don't want it. Not trying to preach (he said while preaching) but simplify as much as possible.
And lastly, yes you are seeing fouling on the outside of the cases (and in you chamber walls) because you are loading so light regardless of the "book" data. I use .5 powder grain increments with 44/45 cases. You will notice a difference in loads without danger using this increment and can then fine tune, if you will, when you start to find accuracy and cleaner case walls (and cleaner chamber walls). Sorry, did the preach thing again.