I've been talking with the webmaster of http://www.vgwiz.com/, and they are willing to design and make some NES cartridge boards for us! Provided there is a demand for them, of course.
We'll all need to participate in the design (we can do that here), so we can get a good and flexible design. As much as I'd want to, I don't think we can really go overboard too much with 4MByte ROMs and such. (Or maybe we can, if someone here knows how to organize the bankswitch logic effeciently!)
You don't need any hardware knowledge to help out with this design process, just answer at least one of these questions:
1. Do you want to put your program on some NES cartridges? The higher the quantity, the cheaper they could be to make for all of us.
2. What kind of ROM size limit would you be comfortable working with? 128K, 256K, or as big as we can reasonably go? (that limit I do not know yet)
3. How about using CHR-RAM instead of CHR-ROM? Bankswitching CHR-ROM would seem to complicate things, because then you have 2 ROMs which need to be bankswitched seperately. There can be cases where this is still worthwhile, though. (like mid-frame CHR switching, a very useful trick).
We need to come up with a design that's flexable, but still effecient (which could make them cheaper to buy). Let's get something figured out.