I enjoy 3 on 3. Of course sometimes it's dull but I think it's still good much more often than it's not. When it's really good, as it was in Edmonton, it's brilliant. I was edge of my seat the entire time. And while of course it's not 'real' hockey and there is a greater amount of luck involved, for me it retains enough of the core elements of the game to still give what happens in it legitimacy. Just keep it away from playoffs.
Shootouts though I have no time for. Gimmicky, slow, often makes even top players look shockingly inept. Don't think they do the sport any favors. I'd increase the OT to 10 mins, and then if there's still no winner at the end of that, just call it a night.