*for context, I play a lvl 75 concentration sentinel. I tested concentration loadout a. I also tested out the guardian for the first time but I won't comment on it here, my opinions on it are similar to the sentinel*
Going in, I had seen the guardian pts release, and had seen all of the unhappiness with it, which upon watching videos of playthroughs on the pts and explanations of the new system being tested, I agreed with. Upon testing the sentinel, it wasn't as bad as I thought, but I still wasn't very happy.
Having no blade blitz and no combat clarity (which the best set bonus is built around) tripped me up, there was no straightforward long-term stun (other than force sweep, which stuns a little bit) but the lack of stuns compared to the game now tripped me up as well. Overall, it felt like a shell of the class, like my character was level 40 or something. This did not feel like a level 75 sentinel.
But to answer the questions, force clarity, force camouflage, zen, inspiration, the concentration abilities (concentrated slice, etc) make the sentinel the sentinel for me, and at least half of those were missing. To reiterate, this did not feel like a level 75 sentinel, but rather a hallowed-out level 30-40ish sentinel. The available abilities were able to get through the Onderan dailies, but would definitely not stand up in harder content like pvp, ops, and harder fps. I'm a half-decent player I'd say, and without those abilities, I would not last a second in pvp and other harder content.
I was originally very excited for the premise of the combat update, but you said we would have more choice (e.g. being a lightening marauder, which I understand is still a work in progress and this part hasn't been included in the pts to my knowledge yet), but so far the 'more choice' is basically choosing which abilities to keep at the cost of others. This is pretty much the bare minimum to have a pve story player have a half-feasible rotation, which will not cut it in really any content outside of story. If the pts where it is now were to enter the game, ops and pvp would just be a shell of what it is. If it is do-able (which I understand it may not be) I would highly suggest having pvp, flashpoints (especially vet and master difficulty) and maybe some smaller ops to do with these abilities, which I think would really demonstrate the cuts you are making.
If you continue down this path of making the other classes like this, I guarantee you that you will lose a significant amount of your player base (the people threatening to leave aren't kidding!). As for me, I haven't been playing this game for long (since Onslaught), but I have really grown to love it. I have put so many hours into this game and have very much enjoyed learning the class combat and refining my skills, and I honestly don't see a need for a change. But if the update come out with combat long these lines, I think I will sincerely have to rethink if I want to play this game or not - I will honestly be heartbroken if you reduce the classes to a hallow shell of what they are now.
Please listen to us - there are literal thousands of people voicing their opinion on this, which is what you asked us to do! If you don't, I think you can imagine the loss in both profit and player-base you will experience.