I tried Dvorak for a couple of weeks and got to OK speeds, but in the end it wasn't worth throwing out the countless hours of experience with qwerty, or the slight discomfort of using other computers and having to switch mentally.
Colemak is way easier to learn than Dvorak if you come from QWERTY. With Colemak, all special chars and some common shortcuts (undo, cut, copy, paste) are on the same key as on QWERTY.
I don't know if I'm faster with Colemak than I would be with QWERTY now for normal text, but it certainly feels smoother and more natural, if that makes sense.
Unrelated to Colemak: I wrote a typing game a few years ago. It's more "playful" than Typeracer and targeted at beginners. I don't think it will improve your typing speed past a certain level, but it should still be fun:
edit: wow -- really impressed. Very satisfying explosion animations and sounds.
So you might have abandoned it too soon.
http://patorjk.com/keyboard-layout-analyzer/#/load/VPDHWn6k
Over a lifetime that's a lot less wear on the hands and fingers.