I can only really speak with any sort of coherence about the Infiltration tree; so, all subsequent thoughts are related to it. I'll also refrain from discussing values/variables, not only because it isn't my job to try to balance the game, but because I don't have nearly the amount of knowledge necessary to do so
I'd say two of the most defining aspects of an infiltration shadow are--or should be--stealth and (shared with the other trees) our double-bladed lightsabers. I don't feel like either of those aspects are emphasized in any meaningful way, and I'd like to see that change.
I see a lot of redundancy in this tree, and the lack of creativity bugs me. Clairvoyant Strike is just an improved version of Double Strike with a better animation: No one uses Double Strike again after acquiring it, for obvious reasons. All that really had to be done was make the top talent improve Double Strike, but that isn't my point: It's more of the same. Or how about Low Slash, a nice skill with different values from Force Stun, and weaker, but still a skill without any creativity applied to it: It's just another 4-second control. My pulse is racing. (Please keep in mind I am not speaking about how useful these abilities are in their current forms. They are very useful.)
Then there's Shadow Technique. When I think of shadows, I think of stealth. This technique has nothing to do with stealth--unless you count the fact that it doesn't break stealth when you activate it.
Now, I understand that we are sharing stealth with other classes, and that is likely the reason why we have so little to do when actually in Stealth. So, it's a shame, but I can live with it. But what puzzles me is how they can look at Darth Maul as an inspiration for our class and not see that giving us double-bladed lightsabers could be an interesting way to make us more than a single-target class (without madly switching targets left and right, that is). Maul's epic battle involved him fighting two Jedi at once, and being an annoying little bastard while doing it. I don't mean we could be a mass AOE class, but even just a dual-target class that deals damage sprinkled with a bit of annoyance (more built-in than it is now) would be an improvement.
Let me give some examples. Low Slash, at the moment a boringly redundant skill, could stun one target and slow another. Clairvoyant Strike, also boringly redundant right now, could hit two targets rather than one. In keeping with the "bit of annoyance" part of the previous paragraph, the second target could suffer low damage and some debuff (lowered accuracy, a DoT, I don't much care). Balance that however you wish, but make it more interesting!
What it comes down to is I don't have a very good sense of identity as an infiltration shadow at this point in time. I'm a shadow living outside of shadows, wielding a double-bladed lightsaber as if it was a single-bladed lightsaber.