@Sci-Fi: Thanks!!!!! I wasn't sure if there was a standardized size, so I was worried that the Dura Road would still be too large. But I have 30.5mm from caliper to fork, so I'll pick up a pair. I'll leave the new MTB pads on the rear caliper. Thanks also for the included picture; it's always reassuring to see a picture so that I know I'm on the same page.
@Metzinger: Thanks for the advice on not grinding them down; I didn't realize there was a steel structure embedded in the pads! Regarding calipers, I found a guy willing to sell me the stock calipers from his Felt F55 (I'm guessing they are Tektro RX20) for $20. I was going to do it, since I assume the calipers are an improvement. But now it sounds like I should pass (?). I must admit that I don't really know what makes for high-quality brake calipers other than the omnipresent lightness concerns (I can see how cable stretch would be undesirable though)
@Everyone: Thanks for taking the time to respond to my question; I really appreciate it!
-Nube