I've spent the past week playing Realm, and have a good feel for the changes, along with many playthroughs of many different builds and skills, and my one very broad suggestion;
The class skills really need to be comparatively rebalanced. Take Iron Spiral for example, that skill is so far ahead of Blood Hatred and Earthquake you'd have to be a complete idiot to use either over Iron Spiral. Theorycrafting feels dead, when one skill can do everything another can but better.
For example, Blood Hatred could probably stack procs, and gain a moderate amount of survivability with its Life on Hit, but why bother? Iron Spiral will just outshine it regardless. It seems like a lot of skills are meant for very specific reasons, but the result is I don't ever feel unique whatsoever. Call me a Hipster if I don't like meta builds, but the point of MXL originally was to theorycraft. Now the skill imbalances have killed it.
Why is earthquake 70% WDM? It hit's twice sometimes, but Iron Spiral at 50% WDM will just blast a target so many times with a nice 360* coverage, whilst Earthquake has 180* coverage. Why should I use Earthquake? The sad magic damage bonus? A 4% base magic damage increase per strength is really low.
Point being, I really want you Devs to take a look at this balance, and ask yourself why anyone should even use certain skills over others. I really want theorycrafting to be worth while.