These days there's not alot of variety in MMOs, combat are very simular to eachother. WoW wasn't the first with the actionbar combat system, but it was the first MMO I played involving an actionbar combat and when it was new I thought it was ok. Nowadays nearly every MMO has a combat system the most popular ones such as SWOTR, WoW, FFXIV all use the same base combat which is plain, stagnant and boring.
The problem is no one dares to take a risk in the MMO market, they think we can just milk out this market of bringing out a generic game on the market that looks just like every other MMO that's out. You could call them WoW clones or copies, although WoW wasn't the first one that invented the actionbar-auto-attack combat. MMOs are very simplistic if you think about it usually 1 to 4 and sometimes some additional buttons if the class you're playing has procs and whatnot. Boss fights are usually straight forward, I have to admit they do take strategy and teamwork, but I think it's time to take things more to the next level than the average boss with voidzones.
What is my ideal MMO you ask? We need a MMO with actual engaging combat where you actually are responisble avoiding attacks by rolling away instead of running outside a glowing red/purple voidzone. YOU controll your character's attacks, no more 1-4 buttons spam but actual attacks. There should be engaging envirement where you can climb on stuff, in many MMOs you can't even get over a rock because you can't climb this really kills the immersion for me. You can jump off cliffs and perform plunging attacks on bosses for extra damage what not, and other crazy stuff. We really need out-of-the-box MMO that really shows you what freedom and engaging MMO really is about!
Well that's it for my ranting.