Have you tried asking to pay for more space? I would be willing to pay for a package somewhere between the 1TB pro account and the very expensive Business account.
Yeah as toomuchtodo mentioned there is no option except business and there is a minimum of, I believe, 5 accounts, so at $15/per user/mo thats $900/yr vs the ~$200/yr I'm currently paying. Maybe worth it as each band member could have their own account, but it's a pretty big leap when I really only need 1-2 TB more.