Just started with a new client. First step, without any other changes was to upgrade to a premium web host. Previously very slow on shared hosting. Upgrade inlcudes CloudFlare Enterprise CDN + Sucuri security suite. Since the move, impressions have dived around 70%. Any ideas what could cause such a thing? Upgraded security slowing down Google bots?
It's probably something related to cloudfare. They might market well and be a good product but I've heard of issues before when moving to cloudfare. Check for seo related problems using cloudfare, have a Google see what you find to check.
Assuming you have everything configured correctly so as not to block the good bots, analytics, and such. It's possible that bad traffic is now being blocked better. Also, could be too soon to say anything as it all needs time to settle.