At this point, you have to start preparing for the playoffs. Lance Moore is definitely droppable at this point if you feel like you would never play him over your other WRs. Marshall and Johnson are must starts, so you have maybe a flex spot for a WR or RB (guessing).
If so and you feel like you can play matchups better with Kap or a TE, then don't hesitate about it. It's not crazy or anything. Realistically, now that the BYEs are over with, you have your lineup that will probably be the same every week for the most part. Of a TE vs QB, I'd rather have the backup QB there because the TE's will be there if you need them and the QB points are much more important.