You will find many different opinions. Trying various things is part of the fun. I use Pyrodex and don't have rust problems. Best to ignore the crotchity posts.
I use Gatofeo lube under the ball, not on top...that's messy. If you are interested in making wads or lube, you can search for Duro-felt and find posts. I use the hard wool felt. I use a hex drive Harbor Fright punch in a drill against a pine wood block to cut them out. I Dremeled the punch ID to the dimension I wanted.
I have purchased Balistol, but have not used it yet. I don't think it smells that bad, but think I could just have used something cheaper that I already had.
Some guys make BP and even caps. Valuable knowledge, but I'm too lazy I guess.
Read lots of posts, try what strikes your fancy. Don't make it hard, there are many 'best' ways to do everything it seems.
I have never smoothed my bores, and would shoot the pistol before changing anything, so you have a base line to compare any improvements.
Since you shoot smokless, you will have eye/ear protection. BP (or subs) is loud!
BP pistols must be like potato chips....can you eat just one?
I believe maillemaker had a Jan 17, 2014 thread about the best wads, that has the Duro-felt link. I bought felt and tallow from her and now have a lifetime supply.