I believe your b/w inked drawings are very nice, but the one colored image I saw needs to be more clean, and background would add back/forground to the character. It'll come with practice. But there are not too many images in your gallery for me to make any decesion upon....
This place is still inactive for the most part, especially in the art forum. You'll have to be patient before others reply. You might get more feedback in SA/DA, but I don't think you won't know how popular your print is until you bring some to the con...
If you ever want people to buy stuff, aside from art being 'good' quality, you've got to make sure some people would recognize your piece, so you can start building up your name by selling things this year, to build up the demand
I mean, if no one knew what "Inu-Yasha" or "Naruto" was, do you think they would buy them? NOT likely. (I know so because I can doodle pictures before it reaches US = no responze. The craze hits, then everyone wants some. )