I always felt the ESEE-4 should be either 1/8" or 5/32" but that is just a personal thing. When they designed it, they were clearly trying to distinguish it from their RC-3 model across a bunch of specs. I thought it was a great knife, but I own both an RC-3 and 6 and like them better in their respective tasks. Anyhow, when I had mine I both removed the coating and did the sandpaper mouspad convexing. It improved slicing performance markedly (no shoulders to hang up on) but I could never get it to be as an aggressive a cutter as a barkie or a scandi. But it is one hell of a tough knife and sometimes that is valued more over fine cutting tasks.
Regardless if you change the edge grind or not, if you decrease the angle of the bevel say to 30 degrees instead of 40 degrees out of factory, you will get a boost in cutting performance. This of course will give you a more delicate edge so I guess it really is up to you to decide which you trait you prefer to have and which you are willing to trade off on. For myself, I prefer cutting to overt robustness.