I Actually agree, i think section like "Services" should be added.
So designers/developers/other service providers can "sell" their stuff there, and all others.
and then the design/developing sections will be clear to only Q&A and not fill with WTB/WTS gfx stuff.
I Think we can create this section with MUST USE PREFIXES like
[WTB] - Want to Buy
[WTS] - Want to Sell
[WTT] - Want To Trade
And maybe...
[WTG] - Want to give? if someone is feeling very generous and wants to give "free" stuff? or just keep this one in the graphics section?