I Just started a new game last weekends went with bViradia this time, with a bit a tweaking its turning out to be a nice ENB. Might have to give that blackout/Onix a try later

Now i use Nevada ENB Realism, for me is the best ENB configuration.

The same thing happened with me, I have tried literally every ENB that is publicly released, but I still am not satisfied completely with the look. The ones that look best in my opinion are old world and dynamo. I   like to tweak the files a little to enhance the look, and that has definitely made them look a lot better.

Old world ENB-Nevada Skies URWL-realism ENB grass file (fallout 3)

screenshots:

Dynamo ENB (orange palette, default sweetfx)-Nevada Skies-Realism grass

Screenshots (lots of pics):

It really depends on how you want your game to feel, but those are my suggestions. I'm also going to try mixing them to get a look like dragbody's game.