Edit
I inspected skill trees again and I found a hybrid tree that solves %90 of my problems.I dont anymore think assasin is frustration , it was my ignorance and impatience.There are still some minor issues but I think game mechanics will shape better in future.
I enjoyed swtor from lvl 1 to 46. I loved story , questing , environment , warzones. PVP balance disappointed me. Its rather absurd , far away from being balanced. I play assasin and I want you share my pvp experience I earned with.
Assasin is a hybrid class , has very limited melee abilities and very short range spells.Assasin uses force like energy of rogue in wow but uses willpower as main stat.Assasin wears light armor.Assasin has 1.5 second GCD
I want to start with deception play. As deception assasin your earning procs with saber strike ( your basic no force required melee attack) and volcanic slash.After you got 5 stacks of discharge proc and 2 stacks of shock proc you are dealing very burst damage with shock and discharge. You have 2 second stun ( 30 sec cd )which is usable in stealth lasting 2 seconds , 1 aoe pushback ability , 1 incapacitate cc which breaks by any damage and 1 minute cooldown cc which can be usable stealthed or not stealthed.The problem is you have terribal survivalbility , you cant live long enough to stack procs.Your constantly snared , cced and nuked.You can go stealth with force cloak ( vanish of rogue in wow ) in every 2 minutes and you have 2 survival abilities.one of them is 3 second lasting force shroud (1m cd) and other is 12 second lasting ( 2m cd ) deflection.You have an melee ability called as maul ,its backstab of rogue in wow and you have a talent to make it ignore armor but its very irrevelant ability.If your cloak is on cd you can simply suicide by jumping from high or stepping in to fire on warzones.
Second is darkness.You are a wanna be death knight with stealth as darkness specced assasin. You can use your stun out of stealth. You have higher armor , you can remove snares with force speed ( sprint of rogue in wow ).You survive longer and you feel like you are a functional class with all cc and survival abilities.Problem of darkness is it has terribal damage. You cant even kill 30 levels lower players then you who dont have most of their abilities.
Third is worst.Madness spec makes you a wanna be mage , a warlock without cc and in melee range.Your damage put is highest in this spec but its heavyly pve oriented spec.
As a conclusion assasin is a wanna be rogue , shaman , deathknight , warlock who cant be any of these classes properly. I dont really care if they buff assasin in next patch because this class requires a whole redesign.