At the moment i use Bumbles on Molly with the only large wraps i have which are cotton bottoms. I normally put in a bamboo booster and maybe a terry one too!
My ds is very slim too and we didn't get on at all well with bumhuggers or huggles. We use bedbugs (my absolute fave at the moment ), night notions and occasionally if the other nappies aren't dry quick flips and stuffies.
Our essential night nappy is a kiwi quick flip cotton terry with a nappyelite fleece covered wrap over the top. Have never yet found anything to outstrip it so we stick with it.