It's not fun to sit around and watch yourself die.
Tanglefoot roots you but you maintain your actions. Daze prevents attacking but you can still move and use items.
Paralysis/Fear/Stun should just be worse versions of this. Game's hard enough when you're allowed to take actions, let alone when you're not.
Ah but the fear of being hit by one of these dreaded effects, will make you feel alive. Nothing than a little "fear of death" to make you feel alive yes?
Where's the danger, the fun, in that?!
Fear is the only gimmicky one really because it can cause your pc to clip through groups of mobs that you ordinarily wouldn't be able to get through.