Agreed. I experimented heavily with different control options and had special configs for all classes and even for some weapon sets. Some things were really good, others remained combersome. Also used the steam controller.
In toughest lvl 5 moments, no tweaking was enough. It was “OK” if you were on the road and with shitload of practice it might have been great.
In the end, I’ve done most of my playing with Dock + keyb + trackball + external display.