My main concern with combos is the server latency issues.
Currently in game there are two situations in the everyday that you need to readjust your position. Mob cone range attacks from the front and rear attacks (ex: tail whips), and abilities that are executed from a certain side of the mob.

For the life of the game, I've been unable to work with these because what the game is doing and what I am doing are never on the same time span. The game doesn't register that I've moved for several seconds, so if I do reposition my character either out of range of an attack I get hit regardless, and my own special abilities don't execute properly or at all despite doing them correctly.
I checked my ping and my connection is solid, I run the game on a high spec pc. Just out of curiosity I installed on a second pc and created a character just to watch my active one and my suspicions were confirmed. Whenever I would move my active character, the other pc didn't display the change for a length of time.

I'm really concerned that if the current build isn't able to communicate fast enough to react that I have changed positions and executed a specific attack with the dependent attacks already in the game, how the twelve am I ever going to be able to do a combo without extreme frustration?