* If you're going to use affiliate links, e.g. Amazon, then you really need the content on your site to appeal to people who have an intent to buy. For example, nobody really comes to Indie Hackers to buy hosting, so affiliate links for hosting companies don't do well. However, people come to learn more about building profitable online businesses, so links to websites and books and other educational resources in that area get lots of clicks. (This is true of any business, really: understand your customer and provide what they want, not what you want to sell.)
* I haven't tried Google Adsense, because I find the ads ugly. But I do use BuySellAds, and the revenue isn't great. I make something like $1 per 1000 visits. It probably doesn't help that ad-blockers tend to block these ads (unless you render them server-side).
* If your audience fits into a valuable niche, individual advertisers are often willing to pay quite a lot for some real estate. Of course, this requires some manual upfront outreach on your part, but it's easier to do than it sounds. I've had 20 minute phone calls that resulted in $1000 or $2000 ad buys.
EDIT: Also, if you're going to run a content site, create a newsletter that visitors can subscribe to. Make sure it goes out at least twice a month, so people don't forget who you are and unsubscribe. (You can completely automate it if you don't want to spend time maintaining it.) Newsletters are valuable real estate for ad revenue, and they also help you build an audience that you can potentially sell to if you ever create a product in the future. In fact, a newsletter can be your entire business: https://news.ycombinator.com/item?id=13630163
Which makes me bring the question, is it worth it?
$3.500 / 100 posts = $35 / post (per month) = $420 / post (per year)
I understand it's a marathon though and that value compounds. When you had 10 posts you were probably not making $350 and when you have 1000 posts you will probably be making a lot more than $35.000.
I'd love to see the associated human costs and how many hours/week you are spending here, doing what and how that has evolved from the beginning (more automation, new challenges, etc).
Is the revenue so far worth the time I put into it? No, not by itself. But everything that I've done so far is really a launching pad for more, bigger, and better things, so I see it as an investment. At the very least, I've reached a point where I can survive on my own and work on my own projects indefinitely. Beyond that, I've built up an audience and community that I love, and I've got lots of plans in the works to try and deliver even more value to them + generate revenue in a more scalable way.
What do you mean by "completely automate". MailChimp or similar tools, or something more automated?