first, nice models AND paint job. well done!
once you have set the painting condition, there are three settings (that I know of at least), that can have a big impact to get tight or wide, soft or sharp, fuzzy or clear "edge painting":
the most obvious: degree, which can be set (much) higher than 100% by the way (can be useful in some cases, and such "boost" can give interesting result when choosing a "less on..." option). first setting on the right of the condition at the top (when using nomal material painting).
next on the right again: 'contrast', positive or negative... the latter can be a better choice in some cases, experiment!
and third, in the smart material editor, you also have "edge scattering", which can be filtered with a texture, or noise. this one, combined with 'contrast' and 'degree', can give interesting variations.
that's the basics, I'd say, but they already offer subtle range of options, depending of what you're trying to get. After that, smart marterial layering, masking, etc, extent the possibilities even more.