There are some things you can look for now and replace, but most I'd just wait until you experience an issue.

GI connectors and headers J120, J121 and J115. Check for burned connectors/headers and replace now.
Replace the batteries with a remote holder or add NVRAM or go to Lithium batteries to prevent leaking on the CPU. Do that now.
Resets. I'd just wait and address these if it start happening. J101, J102, J114, BR2, C4, C5 and possibly +5V voltage regulator.
DMD HV section. Again I'd just wait, but look at the bottom 1/3 of that board and see if it looks toasty. If the DMD starts acting wonky, $5 in parts and some time and you can rebuild that area.

Off the top of my head that's all I've ever experienced as common issues. The rest of the stuff that can happen would be fairly rare unless you did something stupid like work on the game with the power on.