It seems a step forward for Outlaw/sub.
For Outlaw removing the RNG of RtB finisher and replacing it with S&D feels very smooth. on top of that you can still roll for buffs and adjust your rotation/playstile accordingly.
For subtlety it really helps to amp up your single target dmg in pve and sustained dmg in pvp. A very welcomed ability back for subtlety. Really there is nothing to argue here, the spec is famous for juggling your buffs since what? WotLK?.
When it comes to assasination... well, it feels unrewarding, a shore you need to maintain with little impact, boring and not very impactfull. It.just feels like it's sucking the damage proportion out of poisons/bleeds which is your bread and butter.