One thing I noticed is that it doesn't draw zoomed-in images correctly - pixels are blurry. Didn't check if this is Canvas or WebGL, but something in the code begs being changed from LINEAR to NEAREST.
(EDIT: turns out to be a Firefox issue; Chrome shows the sweet pretty pixels correctly.)
> I really think this is an awesome project, but I am old enough (30) to remember fast performing GUI apps and I don't know if I'll ever "get over" losing them.
Same here (I'm 29). I'm getting tired of complaining, this literally feels like trying to turn back the tide of a river. We're doomed to use slow and shitty software until the present web fads go away and the ecosystem stabilizes.