Every time some changes happens in graphic cards, then it needs to be reconfigured.
same as installing drivers in Windows, but better in Linux or Ubuntu as you only need to run a single command & reboot, instead of a lengthy installation process as in Windows.
This is actually not true. If you have the ATI drivers installed in Windows, adding a new card requires no install or configuration.
When does it make sense to just go back to MySQL? Seems like most of your headaches would be solved. Just curious since I know you started there, and then went lightweight, only to find out you had locking issues...
It would make sense to go back to MySQL if there wasn't a simple way to fix the locking issue. And now the locking issue is fixed.