How averse to raising funding later are you? My advice would be to develop which ever idea you think is best, don't worry about advertising revenue now, and then try to raise funding. Then you'll get a salary to support the fam.
Don't get me wrong, I'm not opposed to startups going the self-funded route and pursuing revenue from the get go, but that's almost impossible with ads. If you really don't want to raise money, go with the best idea you have that has some other business model.
Generally true, but if a steady income is a requirement due to family obligations, it's often easier to raise funding and pay yourself a salary than it is to build and monetize a site in the short term.
Well, there's all the typical stuff you'll find here. Launch early, get a few users who really like your product, iterate rapidly. You have to be a lot better than any free competitor because people will choose a free alternative over a premium one if they're equal.
Beyond that, try to think of creative ways to market the site. Going the subscription route is very hard, but if whatever it is you have up your sleeve is compelling enough you can make a lot that way.
Don't get me wrong, I'm not opposed to startups going the self-funded route and pursuing revenue from the get go, but that's almost impossible with ads. If you really don't want to raise money, go with the best idea you have that has some other business model.