Personally I rather dislike add-ons that give too much gameplay signals. I only really want things for damage feedback and probably something like DBM for awareness just because it smooths out gameplay and cuts down on extra Vent noise. Shortcut/macro add-ons are nice, but not really necessary. I think they're worth the potential damage to allow shortcut usage in add-ons, but I would heavily argue that they're definitely not enough to bar all add-ons period. I think the gist of everything I've said to this point can be summed up in this opinion:

The damage done by imbalance from add-ons is far outweighed by the extreme value of instant feedback from damage meters and other resources offered by add-ons. The number of players who misuse add-ons and fail to learn their class ought to be smaller than those who learn/understand their class better due to improved feedback and UIs.


I think there are some legitimate concerns about balancing, and I'm sure add-ons will be misused, but the overall impact of the game should be positive, and for those players who opt for heavy add-on usage as a preference, an overwhelming positive.

(For what it's worth, WoW currently tells you when to cast many spells that are buffed from procs naturally, without add-ons. It's all "fingers of frost! gogo ice lance!" and then you get to decide whether the program's right or not. I just thought that'd be of interest here.)