Feel free to post suggestions here. They will be considered and some may be implemented.
One beta tester suggested adding a 'mixed' category to both the 'Site Format' and 'Niche' drop-down menus.
Although adding extra fields to the menus would be very easy, getting the rest of the software - especially the auto-join functions - to work with the new settings would not be so easy, and there are other concerns as well.
I would recommend using 'general' in place of 'mixed' in the Niche menu.
I created the Niche menu to be somewhat vague, because if too many options are presented and people set their sites to accept auto-joins only from matching niches, then the pool of available trades for any one niche will be much smaller than it would with the existing method. So for this reason, I think it makes more sense to lump things like general and mixed together, and also keep some other niches relatively vague instead of adding many more specific niches at this time.
Likewise, if your site is hybrid of text and thumbs, or of TGP and MGP galleries, then it probably makes sense to select whichever type of site you most prefer to trade with.