Hot streak managing & spell lag broken
The server seems to completely eliminate the spell lag that was on retail, which completely breaks the way the class was played. In case you're not aware of how things worked on retail, let me paint you a word picture: You have one Hot Streak proc, you cast a Scorch and immediately follow with an Inferno Blast. What's supposed to happen is one of two things: either your Scorch crits and you have one free pyroblast and an extra hot streak proc, or it doesn't and you have just one free Pyroblast. This is because the game waits about half a second for that Inferno Blast before registering the non-crit Scorch and resetting your Hot Streak.
This server on the other hand does not wait, it immediately wipes your Hot Streaks clean, meaning that the latter option where the Scorch doesn't crit now becomes just a single Hot Streak with no free Pyroblasts. What this means in theory that either you have to roll a 30%ish RNG chance each time you want a free Pyro, or you have to waste a freeze for every single pyro, which is unacceptable for a class that's entirely based on setting up bursts against frozen targets. This completely ****s the spec over PvP-wise. The only other option would be to cancel your scorch casts each time you score a crit, which greatly reduces the spec's damage, and more importantly makes it a massive bore to play.
</rant>