Making money with Niche is not possible like before. This is what i think.
As I said, I would consider niche sites as the best way to make money online but you should know that the scenario today is completely different than what it was 2-3 years back.
Back then, you could find a keyword, get a exact-match domain, build a site, create some spammy backlinks and get #1 in Google. This is not the case today as you won’t reach anywhere with such tactics. You can get to the first page but that won’t be long before you are penalized and thrown out of search results.
With the constant algorithmic updates, Google has made sure that no site with crappy content stays on top of the SERPs. The focus is shifted to quality over quantity. You can still rank your niche site but not with the way I mentioned above.