Elementalist is probably #2 on the list of professions that have serious problems.
They're kinda a mess right now. For one, their bug list is ridiculously long
. None of them are as serious as non-functioning minions or siphon healing your enemy, but some are still bad.
Arcane Power is supposed to give you 5 crits, and it just doesn't. Certain skills "use" all of the crits, certain skills won't even crit if you're <3 charges (but still eat them), etc. If your Phoenix ever hits an invulnerable mob, it ceases to exist instead of finishing it's loop like it should (because it isn't a targetted attack in the first place). This actually IS a really big damage loss for scepter builds. Quite a few of the profession's skills with boons don't match the time of the actual buff (like 4s instead of 6, 5 instead of 10, etc.). Burning Speed often explodes at the start of your slide instead of at the end, so you can completely miss your target and lose your combo. Another huge damage loss.
I could keep going, but I think you get the point? If all the bugs were fixed, Elementalist damage output would increase by quite a bit.
But even then, the profession has some serious issues. For one, it's a LOT of work, but there's no meaningful payout. You have to jump through a ton of attunements, setting up nonstop combos, just to break even (and not even) with other professions when played by lazy players (meaning, not played well). It's a problem. I'm not against complex professions and simple ones at all--I even think that they SHOULD break even. But it has to be relative. If an Elementalist is going to put a lot of work into their playstyle, then they should be reliably hitting a higher output (in support, control, damage, or whatever) than a Ranger or Warrior does when played half-assed. I think that's fair.
On top of the sheer amount of work they include, they also have trait issues (which I discussed a lot earlier in the thread and I think Sho (?) disagreed with me. But honestly, after a lot more time spent in the game, my position hasn't changed. It's definitely an issue to me that the trait lines for the elementalist are tied to attunements. On literally every other profession, I can go down most of my trait lines with whatever weapon I want and construct an appropriate play style. It may not be optimal, but it'll work. And with planning, it will work well.
You just can't do that with an Elementalist. Outside of the element's spells, the traits in most of the trees just aren't impressive. It's not worth taking traits (which aren't that strong) just for the 7 second out of every 28 you'll be in the attunement. The end result is that any major traits that are limited to a single attunement, barring certain conditional ones, are highly devalued. Because even if that element IS the crutch of your build, it's just too small an investment when you'll spend so much time outside that element.
For instance, Air/Water 25, Arcane 20 is a popular dual dagger build. Air spells are its main source of damage. The Major Traits are glyph recharge, cantrip regen, +20% damage to targets under 25% health, condition removal on water attunement, buffs on attunement, and arcane shield when your health drops to 25%.
What the build is essentially doing is searching out the traits that will be useful at all outside of air attunement. So it takes glyph recharge to lower the heal spell CD. It uses a 75s cd cantrip for temporary invulnerability, so this spec gives them regeneration once every 75 seconds (woo). Just makes the oh-sh*t button slightly better. You only switch to water for your 4/5 skills, so this is an occasional condition removal. And you buff your survivability some.
It's a precision build, so the fire traits that aren't bound to fire are still worthless for it. It doesn't take con damage, so Earth is super weak (and they have a heavy focus on dodging, so the "when endurance is full" earth traits do nothing for them). Obviously they don't want "in Earth/Fire" traits, because they're used almost exclusively for combo fields or finishers (slight caveat is that Earth has some control skills that are situationally useful).
So, really, you're just falling into water. It's the least useful of your attunements, without any finishers or fields, and you realistically only even use it for your 4/5 skill because 1-3 are stupidly weak (through 3 isn't attrocious if you just need to get away because U GON DIE). To that end, you make it remove a condition on attunement. And because it has what is (arguably) the best Elementalist 25 minor trait (2% damage for each boon on you, and Eles are boon machines), you go all the way to that one.
Really, it's creating a spec by choosing what is the least useless. Outside of the 20 points in Arcane, nothing really matters that much. That's boring and uninteresting. On EVERY other profession, stats and weapons and whatever don't restrict you. Even if you don't go for condition builds, there are usually plenty of useful skills in the condition trait line.
For instance, say you're playing Sword/Shield + Staff Guardian. You don't take any fire-based utility skills. Your only fire-based skill is Virtue of Justice, and you're not really relying on it for personal damage. Doesn't matter, you still have a ton of great traits to choose from.
Three minor? Blind nearby foes when you activate VoJ, VoJ is renewed when you kill a foe, deal more damage to enemies inflicted with conditions. All useful even if your build doesn't revolve around burning at all. And only 4 of the major traits have anything to do with burning, only 2 of which (maybe 1--depends on if Spirit Weapons scale with your stats) care about condition damage at all.
Going Fire on an Elementalist without building for condition damage? Have fun with that--the only traits that are more than just token buffs (like might on cantrips) until you get to the very end of the trait line.
That's not fun or interesting. And it makes Elementalist builds the most restrictive of all the professions. They all go at least 10 into Arcane, usually more. And then they're either Fire/Earth or Air/Water. (Caveat 1: there are some pure-survival builds that go Earth/Water, and some specialized WvW builds that go Fire/Air and are intended purely for maximum damage when attacking from the ramparts. Caveat 2: Some builds, occasionally go 10-15 points into might purely because there isn't anything attractive left, and they use the 3-5 skills for mobility).
But, overwhelmingly, the profession has no build diversity. Because it's just far less effective not to go one of those two routes.