Yeah, that's a good idea. I'd insulate the spool from the heated bed though, just in case. In the oven, I'll usually leave the filament in there for a few hours, though I haven't really experimented with how long it needs to be in there (my oven has a warm setting, which is below the 200°F setting).
I also like the Iris watertight storage boxes from the Container Store, they keep out the moisture better than the backpacking dry bags I was using previously.