Very little doubt that the more products you have listed, the more your chances increase of making sales, within reason of course. The thing you have to balance is the outlay for listing in volume against the return you are making.
I would suggest trying that type of strategy where you are not paying listing fees up front, somewhere like ecrater or Bonanzle, or some other free listing site.
Yes, the traffic volume may well not be that of an eBay, but it will be a lot easier on your pocket and save on start up costs if you are still trying to get established in the market.