Carapils will add dextrins (unfermentables), body and an increased FG similar to if not identical to mashing higher. But IME you'd be hard pressed to find much in the way of sweetness. Put some carapils in your mouth (don't chew they are rock hard) or eat some malto-dextrin if you have some on hand. Neither is sweet or has much of any kind of flavor. Caramel malt is sweet and has an actual flavor.
Also, I find there to be a pretty substantial difference between pale chocolate (Fawcett is all I have used thus far) and regular chocolate malts wether they are the 350L Briess chocolate or any of the english chocolates. But the pale chocolate flavor may be just what you are going for. It's a nice malt for sure.