Are you asking about tweaks for recording, or tweaks for mixing? They should be viewed as totally seprate processes. For most recordists, there is very little to tweak "in the program" during recording. The only tweaks in the program for recording are generally selecting the driver, the bit depth, and the sample rate. Most agree that ASIO drivers are the best, that 24 bits is optimal, and that 44.1 khz is the sample rate that makes sense most of the time. Beyond that, the tweaks are more outside the program, setting optimal gain structures and tweaking any HW comp/limiter settings.
If you question extended to the mixing process, well that's a whole other big ol can o worms with tweaks galore, and much too broad a question.
-RD
