Re: disk, I've got a HDD, not SSD on an Asus laptop with 12GB RAM.
I'm using v6.22.3.8816 (08816) Public (CE Build ce-62.6.10954). My EXB file is 6.13GB
Re: rebuild time, after a quick "fix all notes", I clicked on "Optimize database", a progress bar appeared, and it took all day (from some time in the morning through till some time in the evening) to complete. Then Evernote was in not responding mode indefinitely...at some point after at least a half hour, I shut down the machine, rebooted, restarted Evernote, "not responding" was back like Jason Voorhees...shut it down again, restarted again...and now, it appears to be running crisply. Started faster than I've ever seen it start before.
Now I'm trying to do a search. I start typing into the search field...not responding. I force close the app, try to start it again, now it won't even start. Previously, I would have to restart machine in order to restart Evernote, but I've since realized I can invoke the Task Manager and close the Evernote processes that were still running even though the app had been shut down - this allowed me to resart Evernote.
One thing I'm now trying that appears to be helping (as in the last 20 minutes) ...I've turned off both Snippet View as well as Note Panel - there are no longer any images being served in my main list. Sucks that I'm paying for a service and can't enjoy its full functionality, but I need the stability.