I notice that I now have a little more pedal travel before the brakes grab than I did w/the stock setup, but when they grab, they are much stronger.
The 13WL caliper has a larger fluid capacity (it holds more fluid within the caliper) than a stock caliper, or even a 13WE 199mm caliper. When you press the brake pedal, you have to depress it further because you have to move more fluid through the lines to achieve the same degree of movement in the caliper/pistons. Your pedal is going to feel different initially, but once the pads contact the rotor and the brakes grab, it should feel just as firm as it did stock. The difference is that you won't reach that firm feeling in the pedal at the same pedal height.
Now if you get to where the brakes have grabbed, and the pedal still feels spongy, then you may still have some air in the lines. Remember, you can't compress a fluid, so if fluid is all you've got in the lines, you shouldn't have a spongy pedal.
True. I think I will try re-bleeding it just to double-check, but otherwise it might just take getting used to.