[gghootch]

but I don't think it would attract me to advertise with you

I wholeheartedly agree. However, this will change when an actual landing page is in place.

I would like to know that in front side of T-shirt there would not be something opposite of what I would like my brand to be

Manual filtering/personal design for the companies that advertise is probably the first step. Next comes incentivizing users to contribute their own design and let the smaller customers pick their company designs. I think that'll work out, though there's obviously no way of being sure.