Average monthly searches for niche?

I do niche sites and I have a lot of them. The numbers vary wildly from niche to niche. Conversion rates of 1% are amazing in some niches, trash in others. I personally put all calculations in terms of RPM (some guys prefer eCP, but whatever, it's up to you, honestly eCP makes more sense since it's inline with paid traffic calculations.) Once I get the site up, I get links to it, and start evaluating the niche. You really can't evaluate a niche if you're not in it, the advice "stick to your niche" is honestly terrible. Some sites average 2k RPM and from what I understand, that's still technically low compared to what's possible. The range is 100RPM and up, if I can't pull those numbers I usually pretty much abandon the site, I'll update it maybe 2-3 times a year.

So yes, you are "traveling in the right direction." But what really determines my effort is (and what I suggest) #1 I don't want any sites to go stale for too long and #2 I focus most of my time on the sites producing the high RPMs. If one site is producing 150RPM, I'm not going to update it or work on CRO, if a 1000RPM site also needs attention.

I do not use adsense anywhere (not much clickbank either) and always have email capture boxes on the sites. My sites are always 30+ pages of content (usually 50+) and not every page has affiliate links, actually I keep the ratio below 50%, (usually more like 25%.) So pages are funneling internally into landers or cross comparisons. I also don't really care too terribly much about #1 rankings, I just want to make sure I'm showing up in the top 4 on keywords with high commercial intent. Again, I only start to care about rankings when I know it's worth it.

I also don't do any black/grey SEO anymore, although this may change in the future. I have purchased established sites from flippa and consider myself lucky as flippa is loaded with scammers. I have purchased expired domains at auction, basically only considering the name and have gotten lucky a few times and the sites had a handful of links.

Protip: I've never seen this discussed anywhere. If I buy a domain that expired and a bunch of the links dropped or were removed. After I build the site, I will contact every single site that used to link to the domain, saying something like "Hey I know you used to link to <mydomain> and I got the site back up and running again and it's better then ever. If you could please put the old link back I would really appreciate it." I will also do this to correct 404s if possible, but I try my best to reproduce the internal structure as best as I can (or 301s.) If this technique catches on please refer to it as the irawr method

I'm currently working on another 30 or so sites using affiliate programs I haven't really worked with before, or I felt they sucked. I'm sure 25 or so of those sites will suck and I'll end up really focusing on a handful, expecting 1k/month+ from each of the ones that work well. I will also pump any high RPM sites with paid advertising, which is the entire point of doing it this way. Also, if there's multiple affiliate programs for the same niche and I'm not creating a footprint from affiliate ids, I'll actually make another site on the same niche and just host it on a different isp.

Edit: I also have zero sites on "how to make money online." My sites focus on problems and solutions or types of products. The problem there being, choosing which product.

Edit2: My sites have a lot of long product descriptions, notice I did not say review. They are "feature overviews" and I don't make any claims that are not reasonable about the product/service. So I don't say "click here to buy these magic pills that will make you get rich quick." Also, I consider CPA marketing to be affiliate marketing to be 100% clear and I really like to work directly with companies on their own affiliate programs or through the Linkshare program. There's a pile of programs on LS and I think a lot of guys get scared away because there's not tons of information on the programs there. Sometimes I work with a company and I'm 1 of 4 affiliates actually promoting the program with SEO, so I basically roll my face over the keyboard and get on the first page. LS has some pretty insane programs like Udemy, which pays 50% on a sale. From experience, it's easier to get somebody to take a course, which has a lot of perceived value, rather then buying a clickbank ebook.

Do you have a site up already? Is it getting any traffic? Or, at least, is it ranking anywhere in Google? (Is analytics showing you ranking at any position for any keyword?)

If you pick easy keywords, you ought to be on page 1 with just onpage.

Keep in mind things like this:
50 searches a month but you can be #1 just by using the keyword in the page title and url gets you 15 visitors a month forever

1000 searches but you need to spend 2 months to get it to be #4... and you have to keep propping it

Which one is better?

The goal is to get visitors the cheapest way...

Adsense conversion of 9.45 means that for every 100 visits, I had 9.45 clicks on ads. Adwords got on average $3 every time someone clicked on an Adsense ad on my page... Google gave me, on average,, $1.45 of that 3 dollars... The rules said it would give 60% (1.8) but in real life, I ended up with 1.45 (compared to what Google said was average in keyword planner).

You're going in the right direction. Read again irawr's post.