Will I even be able to mine without all 11 snowfields? This is like 4TB of data (according to the file sizes in my torrent client)
You can mine with just field 3 right now, which is 8gb. As the difficulty increases further fields will be activated.
At the point it gets to the larger fields, I expect that people won't mind buying some multiple TB SSDs to put them on as there will clearly be enough interest and probably enough value.