Hi! Actually, just as in most exchanges, participants can ask questions via the mod (i.e., me). However, generally speaking, this exchange is geared a little more toward the writers and artists - and a little less toward the recipients. With rarely-used characters such as these, it's already going to be slightly more difficult than it typically would be to write/draw something and so I want to make sure that the creators have as much freedom as possible to work on what interests them (thus, the ten unwelcome character maximum)
Hmm. I might create a secondary category, however, i.e., all the characters who aren't on the exchange list and who don't fall into the "commonly used" character category. I wouldn't mind if people said nobody from that group as "one" of their choices.