I put coinhive on one of my websites to test it out, but some browsers are starting to flag it, causing trust issues with users.
It didn't make very much, like $20 over the course of a month, and this is on a website with thousands of daily visitors.
I think the only way it could make decent money is if you have a ton of traffic, and I am talking hundreds of thousands a visitors per day.
Else its not worth it.
You might want to think about giving JSE coin a try, it's opt in javascript browser mining which means that when a user is presented with your website a banner at the bottom appears prompting the user if they would like to participate in light mining (10% CPU). The JSEcoin team has already worked with many antivirus providers to whitelist the mining script. Basically it's similar to coinhive except not shady.