All these tips seem like very good advice, but I think they reveal the deeper issue. In a game like this it all boils down to the moment, or "the shot". The instant where everything has to go right. It can be pretty entacing to go looking at your setup for the solution, but for all its positives, the amount of options and variability is probably the biggest hurdle in the game. Every time you "tweak" the config, your fundamentally changing your game and all you've gotten used to. I'm not trying to say you shouldnt tweak it, but dont get focused on your config and use it as the crutch.
I've always thought you had a pretty natural shot Assasin, so I was a little shocked when I saw this post. Find the settings that work well and that you can accept. Then just focus on gettin into the game, and that moment.
P.S. - Its the same gig as music. The DP battle that might last seconds is the same "moment" that's lasting minutes in a piece of music. Just figure out how to bring that concentration into DP. GL