F2P could get at least 12 more blank spots. But, this isn't essential, and isn't much of a neccessity. You can still play without 12 bank slots, as holiday items can be destroyed, but can be recovered back from Diango, or in the crate of marionettes! Random items can be limited, such as frog outfits, which can be kept as frog tokens. Easy items you can attain from general shops such as tinderboxes, hammers, pots, buckets, etc. don't need to be kept in your bank, as it is only an easy 1-2 coins! How much trouble can that be!