Yeah, I like crit fails as something bad happening other than "you miss automatically". Also I like nat 20's having some sort of bonus, even if it's someting small like "you get an extra attack", or "the other enemies around you are a bit terrified". Nothing huge of course.
I don't mind the maps being restricted to the first page. Sure, it'd help the players out int he long run if you put it on every page, but I understand a bit more work goes into putting it on EVERY page. Also, when someone goes to roll, and oh, whoops! It goes straight to the new page. Yeah, that causes some stress.
But this is your game, and if you want to run things in your own special way, I'm down with it as long as it's not broken. Like the general opinion is that it's broken, not if I'm the only one who thinks it's broken. Or dumb.