I think 8x8 is much more valuable for us retro hardware game makers.
Specially 1-bit! We can work around that on two of your paid packs for some part, but a free 8x8 1-bit pack would make a complete "open" C64 development kit possible!
What are the redistribution terms of the Underbase/MiniAdventures packs? If one bundles them as C64 chars/sprites? I guess that is too easily reversed!