Anyone using a BR800 for a soundcard/controller/interface? Suggest Mic settings for record

I have a few decent mics now but still find less than satisfactory results. So far.
Before abandoning the BR800 for some new interface hardware (preamp) I thought I should thoroughly check out the adjustable presets (COSM FX) for microphones that are in it. I'm told it should work fine.
But I feel overwhelmed by options and settings and would like to know if I am chasing the wind or not.
This might be too specific but surely I should get something decent from an SM7 or an SM58 or an Apex 460 thru this things settings? I mean it has all kinds of limiters, compressors, dynamix, pitch control, EQ, Noise suppression, etc.
So far I tend to get better sound out of the BR800's on-board mics than the "good" ones!! Maybe because they are matched to the machine, but likely because I don't know what to use and what to avoid.
My stuff is mostly R&B, blues, funky pop, singer songwriter. So pretty straight up but usually shooting for warm, close and real.