I think you need to ask yourself what you want to gain from making another booking site.

You'll be competing with massive companies, and you won't have any real advantage over what they can do.

You'll need e-ticketing, credit card processing, customer service and lots of other stuff.

I 'd suggest sigining up for more affiliate programs from these sites, and hand picking the best deals from them. That way people still book through them, but you make a few bucks off bookings.

I don't mean to make you depressed, but unless you have something really innovative, I don't think you'll ever see a single booking, even on affiliate links. There are just far too many similiar sites out there who have been around longer.