I can’t stress that enough. 5v5 and 5M, being what the game is mostly balanced around (Hellgate PvE Dungeons coming out, 5v5 GvG, hellgates) means that damage is weighed equally with utility.
Without utility on your weapons, your armor is the only other place you can find it. And any other player with that same armor but a more useful weapon is instantly a better option.
Without AoE, and I know that AoE is broken right now, your putting out very little overall pressure when your only do single target with some free Albion Online Gold, and that single target damage sits behind an 6-8 second ramp up, that youre easily peeled from.
In order for daggers to be anything other than this cheesy E machine every 20 seconds, they need a reliable CC, and some AoE pressure.
Daggers do not need a invisibilty on their Q. Because that would push daggers into Light/Medium category too much. I agree that there need to be an alternative Q, and I agree that it needs to be a 3 stack bleed. But I think it needs to be a AoE 3 stack bleed akin to Hoarfrost/Cleave. This would give daggers some from of AoE without it being a focus of their kit.
I don’t think that daggers need a stun, nor do I think they should get one. I think they need some disruption, and some soft cc option on their W. Drop Dash completely it is worthless.
Make infiltration instant with half the Area of Effect. Give them a Smoke Bomb than silences those who stand in it, giving daggers some synergy/reason to go heavy chest. And give them a Energy Drain akin to the wraith mobs on hit for their 3rd W.
Keep Slit Throat but lower damage by 10-15% and have it not consume Q charges.