Firstly you don't only brew kits, you brew kits, as do I. Don't get caught up in, this sort of brewing is better or worse than what you brew, we all brew beer, if people don't like what you do, that's their problem. For kits I'd recommend brew enhancer or spray malt, table or brewing sugar will thin your beer out. I use Brew Enhancer and then bump up the ABV with, honey, Golden Syrup, Treacle (stouts) muscavado/brown sugar, and I've used table sugar as well. For priming, I use table sugar or whatever the wife's bought.