Time definitely plays a huge roll in blunders. Actually if you look at the first graph there's a spike in blunders around 2800 which is entirely due to a single GM (Caruana) playing a string of blitz games this year in which he made several blunders.
Blitz games? Is your data from Blitz games played on an online server?
I like the idea of your research, but blitz games are garbage and online ratings are frequently meaningless due to abuse.
You should also look at replacing Crafty with Stockfish. Stockfish is still open source and it's around 350 points higher than Crafty which is a huge amount at this level.
