In general listing a bunch of problem in one post where they are very different, and may need to be in different forum sections won't help you get the best help.
For issue #1. I suspect this is unlikely to be a Pro Tools issue by itself, I'd guess Eucon. Try uninstalling Eucon and see if it goes away. If it looks like Eucon then post in a relevant forum section. (EDIT: I see you fixed that, great).
For Issue #2
Start here:
https://avid.secure.force.com/pkb/ar...ve-errors-9071
Did you do a full clean macOS install or has this system been upgraded with in situ macOS upgrades? If macOS has been in situ upgraded then plan on doing a full clean install instead of beating your head against problems. Maybe get started now doing that on an APFS container if there is space on the boot drive.
What sample rate and IO buffer size are you running at?
What do your sessions look like... how large and how many HDX vs native plugin instances.
What make/model/spec drive(s) are you recording to? what is the disk cache size? are you letting the disk cache fully load (disk cache meter goes green) before using pro tools?... one of the possible causes of an initial CPU error. With an older Cheesegrater I especially want to see you are not on a slow HDD, which can trip up 9093 CPU errors... unfortunately so can other things... and there are multiple threads about HDX systems with 9093 errors you can look at on DUC.
When you say optimized... is *everything* done, WiFi disabled (you said yes...), bluetooth disabled, etc. get every last thing done.
Are all your plugins up to date/compatible? What happens when you remove all .aaxplugin files, and trash prefs, and test with the demo session? (Pro Tools will put back the standard plugins automagically).