I kind of doubt a wad would have any more resistance to the flash and fire ball than a proper fitting lead ball. An other issue is shooting may cause some of the wads to move around and hang the cylinder up on the barrel base.
I used to use crisco and some goopy yaller looking bore grease stuff years ago but got sick of the mess that also seemed to attract loose powder from loading. Have been shooting with no grease for years and so far (knock on wood) it has not been a issue.
Any more I pretty much just shoot cartridges in the things and have yet to figure out any kind of a lube that would work with a wad that will lube things up and not make the cartridges fall apart. But oh well, experementation is half the fun of these things.