Yes, compiling from source is fun and you can often gain a better performance if you do it right. Actually, my system currently runs at about 50% load, so a few extra percent of performance are not absolutely necessary (but a 10x slowdown would not work). So your suggestions, which might be reasonable for your many workstations, would be out of scale in my case.

Also, no nightly runs of yum, just set up iptables and only allow ssh + http. If there is a security problem with one of these, it will make big tech news and I fix my server easily. Even if it is down for a few days, I will not loose thousands of dollars, so this is a small and acceptable risk.