Believe me, it's very hard to play vs 1900+. I have given my best, but seems there is no chance to win.
I don't want to imagine playing 2000+. I know I will lose. So it's best for me ("for me") to play for a draw if I can.
Now I know what GM's like. They are not ordinary human.
I have been over 2000 USCF and two things helped me:
1. Did many many tactical puzzles
2. Had an opening repertoire that I knew very well
How to get over 2100? Don't know!