Another thing I do that annoys my players (distinct from annoying their characters, which is basically my goal), is:
3) Changing the rules This one comes from my tinker tendencies. I like to play around with rules. I find a new house rule, a cool adaptation of another rule, a "better" way to do something, a new supplement . . . and I want to incorporate this. I like to fix errors and oddities, and change a one-off house rule into a constant "let's do this from now on" and then need to fix that, later.
This one, I think, isn't really worth it most of the time. Not for small changes, anyway. It annoys the players and it's inconsistent. If spending points now is worse than spending them later, you'll spend them now. Etc. Generally, if a rule isn't grossly broken, I think it's better to leave it alone. I have gotten much better about this, and I tend to leave a ruleset in place for as long as possible unless my players tell me we need to change it.
Still, sometimes you just find a rule is freaking broken and makes for bad play, and it annoys players who feel you are nerfing their cool attack that unbalances the whole games. But in that case, it may have to be done. Maybe you house ruled something on the fly and then the players prove it's a repeatable and unbeatable tactic - then you need to fix things. But too often you end up Belkaring the PCs and no one likes that.