Never tried Williamsburg or Park Slope, but finding a good apartment for decent price is very hard no matter where. Of course prices drop if subway is harder to get to.
https://newyork.craigslist.org/brk/abo/d/fantastic-1-bdr-apt...
Granted it's Craigslist so who knows how legit it is, but if you're willing to share with roommates/etc. I don't feel like it's super hard to find a great apartment if you're willing to live further out.