a niche i perceive as something i can market
good pics/text on tour
good colors/layout
at least semi regular updates
enough content in the member area to keep members happy
minimal traffic leaks

at least 50% revshare or $25 no-console however in the past i have let that go lower and still made more money than with other sites in the same niche because the content and layout were good, text was solid - and if revshare, because updates were 4 times or more per month for a normal niche or 2 times or more per month for a really scarce niche.

we've often made more money with sites that pay less because they had more appeal to the surfesr.