UA: used to do 6k w' 12K crits on dispel and being silenced for 5 sec was scary in wotlk, doesn't do much more than that now when someone dispels but HP has gone way up. To boot dispel resistance was taken away from the entire tree. If UA isn't a dispel deterrent anymore either the deterrent needs a buff or it needs to be instant which would make it at least even footing vs dispels. Putting this up instantly would have been too much before but now its not a big deal in pvp and pve became overcomplicated/even less mobile due to ISF.
Haunt: locks have the only 31 point talents in game that have both a cooldown and cast time. This does next to no damage but sets up a debuff and does a small bit of healing. PVE this means a lock's rotation falls apart if he has to move (3x stacking SE) in the narrow window of time between when the cooldown ends and the buff falls off. We are now forced to ISF cast every 15 secs so isn't adding more to that a bit over the top? PVP this means when focused you can't even get out close to full (slow) dmg and you are ALWAYS the zerg target of every melee. With what DK, warr, feral does in terms of damage I really don't think haunt being instant is significant.
I will say having both instant would be too much but one of the two needs to be changed. PVE we have a horrible rotation in all 3 specs so giving a bit of an option to do something to at least keep up with it while moving isn't out of line. As it stands affliction has one instant cast every 24-28 seconds in pve, I can't think of a less mobile class with more to keep up with. PVP, if I have no way to peel the melee off me who is spastically running through me trying to exploit cast facing and just trigger fingering their interupts how do I even get damage out?
Overall it seems time locks got a bit of instant casting when compared to other ranged and casters in both pve and pvp.