The idea was to have a store, rather than a marketplace; but i would definitely keep that option in mind.
Escrow was the plan for more expensive items, but I was planning to start selling smaller items to start out (lens filters, sd cards, film, flash cables/triggers and the like) probably with an option for escrow as well.
Why not save some resources and sell through bitmit?
Bitcoin is in its infancy. We are facing a problem: new businesses have a hard time surviving due to small user base, and adoption is slow because not many businesses accept bitcoins. Therefore, at this stage it is prudent to stick together and grow the economy.