With MoP we also got shadowblades, how do you feel that worked out?
When I first think about it now, the first thing that came to my mind was it's a great CD.
But the more I think about it, the smaller becomes my appreciation for that skill.
I can't speak for PvP outside of combat because I only did casually pvp this addon and only during 5.4 about 1.8kish arena rating after I quit pvp with the 5.0 disaster.
So I'll just talk about it PvE wise. As Assassination there is some though to it. On the pull you use it with Vendetta and procs and probably lust. And then you can either use it as soon as it gets ready and then with the 3rd Vendetta again or you can wait and line it up with the 2nd Vendetta, leaving it 40-60s waiting, depending on readiness level.
There is some though that has to go into it and I like that - however you can calculate the best timing of that on most of the encounters before pulling the boss, while most people don't bother with that kind of trouble, it's not a decision you have to make during the encounter most of the time, and even if you make that decision during the encounter, after the 5th pull you know when to push the button like a kind of muscle memory.
For Combat its worse in my opinion. Just use it with Adrenaline Rush (AR). When you think about it is just some kind of improved AR, SUPERAR (insert bad pirate joke). No thinking involved, just watch out for 3 CP Sinister Strikes. The only gameplay to it is that AR lasts longer than Shadowblades and therefore the 3 CP Sinister Strikes turn into regular 2 CP at most.
For sub I feel its the most engaging. On the pull you have to decide on how you use it, but once that is settled there does not go more thought into it for the pull. The consensus is to use it on pull during cds, however while I use it without Dance on the pull and delay the first dance until FW almost runs out, some use it with dance. And during the fight itself I use it during FW downtime, unless we need burst or I will have extended periods of FW uptime or I will get a trinket proc from ICD Trinket soon. Hold on to it after a dance or even use it during a dance? Wait for FW to fall off? Just got a Sleight of Hand proc, wait even longer or just go?
Do you think they should leave it as it is? Does it need more to it? Does the sound annoy you? I like the sound, I can always hear when a fellow rogue used it and compare it to my usage^^. Are you happy with the visual?