I couldn't find this among the list of hotkeys/shortcuts so I suggest to included shortcuts to open and close individual pallets. If It's already there somewhere, maybe someone can point me to where to find this.
PaintStorm is my favorite art app on the iPad now. I think though, ProCreate has 2 big advantages right now. 1. Abundance of good brushes and the community of people making them, and performance. ProCreate's performance is unbelievable. But PaintStorm interface is much smarter. Some things are strange, but overall, it's a lot smarter. It's so much faster to just grab a selection tool and scale something than in ProCreate which tries too hard to depend on fiddly gestures and multi-finger gestures for too many things. Both are still magnificent apps though.