storage space and bandwidth are not really limiting factors on today's internet. i have over 100gig of online storage and 25mbps internet, for example. (corrected 1gig to 100gig).
Like djim said, storage space and bandwidth are non-issues.
May I suggest trying to get Sharefest popular within a niche? You may have to adapt to that particular niche, but I think it'll help you a lot.