Cat 4 crit? You're gonna wreck at some point. So don't ride anything you can't easily replace financially. If you can replace the Diva without sweating it, just race it.

Otherwise, look for a cheap CAAD9 or CAAD8 or even CAAD7 frame. You're good to go. Believe it or not, this affordable aluminum frame will likely outperform your more expensive carbon Diva in a fast paced, technical criterium.