I think the key is 'variety' rather than sheer number of listings. You may have 5,000 listings but they (admittedly on a quick look) appear to be much of a muchness. That is - they are fridge magnets or variations on that theme. So, regardless of the number of listings you have up, someone still needs to be in the market for that specific type of item for you to get a sale.
Maybe the way forward is to 'Diversify to accumulate'. If that does not suit a seller's business model then maybe they have to accept that eBid is not viable for them as a sole venue.