For temp control I'm talking about keeping it at a more stable temperature. Not letting it fluctuate thermally too widely. If it's in an area that goes up/down ~10F every day, that's probably a bad thing. If it's just a few degrees, it might not matter.
From my understanding, if you do the 2 week carbonating on CO2/gas method, once it's carbonated, you can disconnect it from the gas and let it sit for an extended period. Again, you'll probably want it at stable temperatures.
For long term aging, as long as the temperatures are right, you should be able to go years. Revvy has a barleywine that will be aging for ~5 years... Most of the time, people age like that in a wine cellar (or a cool cellar) type environment. Or an artificial one. If you have a place where you can keep it at 50-55F for an extended period, I would go for it. I would also probably toss some oak into the keg you age in. I wouldn't use a carboy for that long. Mostly because I wouldn't want to have to worry about the airlock. Or worry about something knocking it over and spilling it. Or if a glass carboy, something falling onto it and breaking it (or cracking it)... Better to use a corny keg... Once it's all done fermenting, and tastes in line, rack to the corny, toss in the oak, then set it in the aging chamber for the duration...
I'm planning on aging some mead in corny kegs for 4-6 months (maybe longer)... This will be starting pretty soon. Need to get the location where they'll be aging worked out for when I put them into the cornies. Then I'll just label them up and set them aside... Come end of the year, I'll sample and decide if they're ready for bottles yet.