30GB is nothing. Neither is 60GB, assuming that much more for the exotics. A 120GB drive is $20-25 USD. It seems very possible to me.
The thing that I don't like about the "one torrent per artist" approach is that you end up getting very few seeds for obscure artists. And as the subject says ("HVSC for Amiga") the idea is to have the most complete collection possible.
EDIT: Is MODLAND's stuff compressed at all?