I use a LOT of mods. From your standard UI mods to Tootip mods to mods that let me know if my party's being attacked (and by whom) to mods that tell me who my target is attacking... except for the minimap, my screen doesn't even look like a standard WoW screen.
One of my biggest problems in groups/raids is retaining aggro on multiple targets. So I found a mod called HateMe, which basically simplifies the Warrior rage-generation experience. What worries me is that I think it might simplify it TOO much.
What the mod does is make a hotkey that, when clicked, goes through its calculations and generates the best rage-generating attack for the situation. If the mob's below 20% and I'm in Berzerker or Battle stance, it Executes. If I'm in Defensive Stance and Revenge is up, it casts that. If I'm in Battle Stance, the target's not on me, and Mocking Blow is up, it casts that. If all else fails, it casts Sunder Armor.
Now, it does NOT cast everything... many situational powers (such as Shield Bash, Challenging Shout, etc) still need my input, and I don't HAVE to use HateMe (meaning, it doesn't disable my other buttons, or autocast or anything like that) and I can REALLY see the benefits, along with a couple other mods I have (one called CombatSentryGizmo shows all the enemies causing damage in the area, so I can click on their bar instead of having to find them on screen, so I could click that, get close, and instantly cast the most rage-generating power I have) to keep aggro on me, where it should be.
But there's this little part of me that feels like it's pretty cheap. Still, I think mods are in the game to simplify and streamline gameplay (as well as your class roles) and I think Blizzard definitely supports their use, as long as it's not some third party farming automation.
Anyone else have any similar experiences where a mod seemed great but... maybe too great?