I’ve always found obsidian to be a challenge. Yes, it knaps easily, but I think that’s also the problem. And, I’m just not much on glass. It’s messy. There is a reason why I’ve heard it referred to as “obs#*tian” in some knapping pits. But, done right, they are sharp points, no doubt.
Keokuk can get funny for me, also. I dunno...kinda chalky or something. Just doesn’t play nice for me.
That’s just my perspective, though. Different strokes...
Dacite is like a slightly glassier G’town. G’town was what I really cut my teeth on. A little went a long way and it has that sweet spot, right in the middle, for characteristics. Only problem with it is it only comes in one color!