Jeff i would keep it running for another year if nothing else fails in the meantime. THe old 1ME's were notorish for there heat issues and on board power circuits fail due to overstressed by heat..
It is 1 X layers multilayer pcb and hardly nothing you can repair yourself on those units.
Sometimes going to a different firmware version will give you options back because of a reflash and config of some components.. Whatever you do.. DONT!! install 4.6 This will kill all analog and downscaled outputs on the old 1me. And they dont come back after a different firmware... Units had to go to BMD for a swap.
If you are fine with the way it runs now.. Keep it like that.. Those older machines are maybe better to keep this way then to try a update. Because if it fails. nobody can help you and it is a trow away as the Support is gone on those units.