I don't think anyone else has mentioned this, but in my experience the kick drum usually projects away from the drummer making it much harder for us to hear it. Before you just try to make it louder I would check with others as to how it fits into the mix from the audiences perspective. If its not loud enough from their perspective then increasing the physical volume is fine, but if its fits in then you need to find another way to monitor it (such as the BumChum etc).
Maybe even try changing your beater angle. I played a gig the other day where I had to just jump on the kit and play with the owners breakables. His bass drum was really quiet, and we went into a 7/4 section where it's important to be able to hear the bass drum as it's easy to get lost. However, no matter how hard I hit the bass drum even I couldn't hear it, and it wasnt miced. I was literally lifting my leg up and slamming it down, but nothing. I think it was because the beater angle was too small. That, and felt beaters.