I actually try to limit the number of 1/35 dio's I do exactly because of the issue of storage; I only have four of 'em, and I always limit their size to about 14" X 12 or so, in order to fit in my bookcase which I built for models. I do however have a larger amount of 1/72 dios/viginettes, and they are all no larger than 8X6". I always use plaques for bases, and limiting the size gives you a nice, tight presentation.
I have to admit that when I go to shows and see some of these dios that span 3 to 4 feet, I always wonder where and how you can store something that big; I mean it should be covered to keep dust off...I think that limiting the size to something you can fit on a bookcase shelf might help for future storage.
As far as a market for them, I had a guy offer me money once for mine,but that was a "Best of Show" winner, and in any case, I just can't part with them. I think you might find a buyer for them; you might go to a show and spread put a little card next to it saying "for sale" if the club would allow it, or you might try posting them on Ebay and see if you get a hit--then there's always that issue of shipping them!...