There are many issues I have with the soulmakers as a whole (I main one). It's an extremely fun class, but it's also tricky to play well.
Firstly, all of the abilities aside from the DPS tree are underwhelming and feel as if the GMs made a last minute decision to weaken the class as a whole.
Our Soulmate Awakening is far too short with too large of a cooldown in between. (I'll call it unfair because Assassins have an equally powerful form with no cooldown and a permanent state)
Our links are too short and must be targetted exactly like the Priests ME (Which is sloppy design considering the links could just reach out or just be a buff without any sort of direction)
For a group buffing class, our best buffs are single targetted, (the "best" of which is broken.)
Our (arguably) best technique comes out of our HP, a whopping 10% at that.
Our second best (once again arguably) can only be used in a 2 minute span every 10 minutes and is easily able to lag out entire raids. Oh did I mention I can only use it for 2 minutes in a 10 minute time frame? If I did, I'll mention it again, 2 minutes total then we must wait for the long cooldown before we can go into our awaken form again and use it again.
Cure pearls are garbage for anything other than placing bubbles for cheap laughs.
Everyone wants our links, but no one wants to be within range of them. (I'll chalk that up to ignorance of how the links actually work, regardless, the links need a wider range and need to be able to link more than 5 people, seriously we're in 10+man raids, why would I only be able to link 5 people?)
Mental Breakdown and Soul Extortion are both pretty much identical with one costing significantly more SP and allowing you to move and shoot.
Soul extinction has a casting time and it's our ONLY DoT.
Soul Injection debuff is solid. I love that thing.
Soul Link devotion is broken in every sense of the word. Also I don't know what they expect us to do with it. Considering how strong bosses are, there's no way it can be used efficiently. Sure it prevents death ONCE, but after that the target will just be wiped when Maya P or something uses another AoE, which she frequents.
Over all, there's alot of reasons why this class is extremely underpowered and needs some rebalancing, fixing, tweaking, what have you... HOWEVER!
I love this class, it's probably my favorite out of any in the game. Plus, who doesn't want to run around with horns and a tail being all cute n cuddly, right? =]