Fruitcake really does need to age a bit to be at its best. Honestly, a freshly baked fruitcake is disappointing.
I think they’re best after a couple of months. Make them in October and serve them at Christmas, and you’ll be amazed at the flavor.
You can age them too much. I’ve read crazy recommendations about aging them for years like a fine wine, but clearly that is bad advice. I kept one for a year, just to see what happened, and I was disappointed.
I would say 3 weeks is a minimum curing time. I’ve served one after only two weeks, and it was noticeably less complex in flavor. I tucked it away for a couple more weeks, and the difference was amazing.
I will say, I’ve never gone to great lengths to wrap mine. I drop the cakes into glazed loaf pans, pour on some liquor, and cover them with plastic. I put the pans on a plate (since some of the liquor tends to wick over the edge), and keep them in a dark, cool place. I keep an eye on things, and re-wet if I think it’s necessary.