I absolutely agree that Eve is a mess right now and deserves buffs.
Since S4, though, I would argue that oppressive burst with DFG was not the cause of all her ridiculous nerfs. She's been nerfed into the ground because S4 vision changes made her too difficult to ward against in the jungle.
Eve spent something like two years as the worst champion in the game (season 1 & 2). She was originally slammed with the nerf hammer because her stealth ganks were too unpredictable, and forced people to simply play passively all the time in the laning phase.
I would argue that her current stealth does the same thing. Pink wards are expensive, and they are incredibly easy to kill. There is no practical, cost efficient way to ward against Eve at the moment, so people simply have to play passively during the laning phase to avoid being killed by her.
I don't think Riot will buff her until they find a way to make her stealth less oppressive. Until people can effectively ward against her, she is going to be kept weak.