All my baitcasters have braided line. I typically tie on 5-6', the leader is basically from the tip of the rod to the reel so it varies depending on rod length. I always want the braid to be a smaller diameter than my leader line and I want it to be at least 2 line classes stronger than the leader. I want it to be smaller because trying albright knot variants work best with dissimilar line sizes and makes for small connections. I want it to be stronger because there is no stretch in the braid, 12lb mono/fluoro can be stronger than 20lb braid because the shock absorbance and stretch and I don't want the braid to be weaker than the leader otherwise might as well be using a lighter leader since these aren't toothy fish. I prefer 40lb braid for the 10-20lb leaders I tie on, I just like the diameter of it and the thin stuff just doesn't cast as nicely imo and has a higher tendency to dig into itself. Braided line is the truth, amazing hook sets, amazing sensitivity, extremely castable, you're on the right path.