If you're going to use a lot of rye, that's another reason not to use carapils. Rye gives a lot of mouthfeel. It also tends to produce some stuck mashes. If you can add 1/4 lb of rice hulls, I'd do so, although you're not doomed if you don't. If you've never done all-grain before, I'd assume your efficency won't be great. You can add some more 2-row, keep some light extract on hand, or just accept whatever you end up with.