I am always willing to learn. I just added considerable AC to my own warrior by recharging his Power Source. So I will concede that it's worth the effort to learn about their use, especially as you can make the one time "intellectual investment", write it down and then just have to find your notes whenever you need to recharge it. I guess what's frustrating is Sony's EQ developers have a tendency to go "hog wild" with some aspects of the game, making MUCH more complicated than it needs to be. Did they REALLY need to make such an exhausting variety of power sources? Do any other than the couple or 3 that boost AC, HPs and/or Mana ever get used, especially as most of them have NEGATIVE buffs built into them as well.
Well, considering the fact that many people don't have access to Pure powersources (which require raid flags), having a variety of 'translucents' was imperative. Also, for every PS you think is 'useless', someone else will get use from. The reason for a wider variety is choice. The more choices available, the more people can build their characters the way they want to. I mean sure, I think the Air and Decay orbs are useless but I'm sure there's some (misguided) soul who finds them useful.
Consider also the Fellowship campfires. I mean how many groups use anything other than the +HP campfire, yet there has to be over 200 different options. Would anyone really want to buff the entire group's CHA, or turn them all into pumpkin-head illusions? Yeah, I did the latter ONE time for laffs but that was it. In fact, since campfires expire with no warning (meaning after a wipeout you may no longer have a campfire to click back to) and the basic no-buff campfire lasts MUCH longer, these days I only use that one. It costs nothing and the "buff" campfires have suffered from one of the other common problems in EQ: failure to rank up the benefit levels of certain buffs as the game grows and character's stats increase exponentially.
Most of the time, I use the illusion campfire buffs (especially Fae) since, as you mention, the feature hasn't aged well so the buffs aren't as useful as they might have been years ago. Honestly, when even trash armor has Faerune on the head slot item, who really wants/needs a faerune campfire? Duration doesn't bother me much either since I tend to hunt in the same handful of places (so always have a teleporter or mage bound there).
More choice is never a bad thing. Even if the additional choices are useless to you, if anyone else finds those extra options useful, it's a good thing. The worst thing an MMO can do, in my opinion, is force everyone down the same path, removing any and all semblance of freedom from the gameplay.