Chelsea_W and apena : Based on your suggestions, I am disabling Wordfence.
I'm following recommended security guidelines (correct file permissions, login protection, disabled XML-RPC, backups) and behind Ezoic's own security measures (like Cloudflare). Hopefully this is enough to guard against vulnerabilities and Wordfence is overkill.
Based on my quick testing, disabling this made uncached pages (bypassed) pages about 2x faster in general and has eliminated spikes and timeouts. Before, I was seeing it take > 30 s and timing out at some points. Now it's returning in 200ms. Maybe Wordfence was a resource hog and causing performance issues all along? I'll keep monitoring this