Brown sugar will not add sweetness, but it will up the abv. For sweetness add some caramel/crystal malt. 4-8oz of an L40-L80 adds sweetness with some caramel flavor and body. It will make your beer darker. It will have a very small effect on your abv, so you may want to add the brown sugar anyway. There are lots of recipes that include both crystal malts and brown sugar or molasses.
Stop using so much caramel malt. Your beer will thank you.
(yes, Carapils is a caramel malt...so is Special B)
pujwI HIq Mild Ale
KPA Khitomer Pale Ale