This thread has become a GFY classic and I have been following it for a bit. I run both paysites and thumb tgp's and I could make a few comments on this.
Firstly, unless you are making a living as an affiliate don't expect having a TGP to make things any better. As much as it is about traffic it is even more about selling the right thing. A TGP loaded up with 2000 hosted galleries is probably loaded full of crap. I use my TGP's to sell my own sites, and I fill it out with some of the better hosted galleries. Sales to my own sites galleries are waaaay higher than the shaved up hosted galleries.
Secondly the productivity you will see from purchased traffic is very low, often less than 20%. That means for every 100k uniques purchased only 20k will actually click on something. Take that into consideration in your calculations.
The last issue is actually managing traffic. It is very difficult to find anyone of consequence who will trade with you. In my case I get a lot of guys adding trades, but most of them can't even send a 100 hit minimum in 24 hours and the trade script just drops them off. The guys who have real traffic will have to be schmoozed for a trade.
Anyhow if you can send more than 500 a day I have a 50k PR4 site accepting new trades right now, let's see if I get any.
American Underground
www.undergroundtgp.com
http://www.undergroundtgp.com/cgi-bin/tm3/signup