All combos are useful. Even if you just spam >>^z until they drop down you still earned about 40 MP and some damage since I think they'll get knocked down after 8 hits. Oh... I see :/
EM actually needs the new Meditate in PvP since all of her combos rely on MP and many combos rely on heavy MP. So a good ammount of starting MP will be good for combos. I'm not worrying about Meditate just so you know since that skill actually balances EM since she's extremely bad in PvP right now. After all, why do you think you see so many EMs spam MM? Because only some extremely good players actually can do stuff and EM also rely heavily on juggling the enemy in the air which is REALLY hard if it lags like it does for me but I still try to combo since I don't even have MM with me in my skill slots when I try out PvP with her and charging MP is EXTREMELY hard when people chase you since you waste shitloads on spamming Teleport all the time.
I'm worried about Lightning Shower, Water Cannon, Chain Lightning and Ice Balls.
Lightning Shower is an overpowered starting skill since it stuns in a LARGE range.
Water Cannon doesn't even knock down from what I've seen but it deals a pretty low ammount of damage if I remember right.
Chain Lightning is like MM since it aimbots and it's quicker than MM since it only lasts for 2 sec so it deals its damage instantly instead of slowly like MM so expect LOADS of damage from that. MM and Chain Lightning will also be 200 MP skills now instead of 225 MP which MM is right now.
Ice Balls got a shorter range but I expect them to travel a bit slower as well? I haven't checked into that. They deal about 33% more damage than normal fireballs and they also inflics frostbite for a little while.