Coming from the perspective of someone who runs a “multiple WordPress theme shop,” as with anything, each business model has its pros and cons.
Having multiple themes can be tough to maintain. If WordPress has a new core feature (like Gutenberg), you have to apply that to each of your themes, not just one.
You might be able to get around this by going the framework/child theme route, like Genesis, but I’m guessing each child theme would still have to be checked to make sure new features work as expected.
On the other hand, all-in-one themes (I like to call them Frankenthemes) aren’t necessarily easy to maintain either because they tend to be much more complicated to meet the needs of a broader customer base.
With that said, I often hear of other people who don’t buy my themes in favor of these Frankenthemes “because they have more options.” These people like to tinker and customize their themes extensively without writing any code. That’s fine, as this isn’t my target market. But if it sounds like yours, then it’s something you may want to consider.
I think you’re on the right track by trying to position your product as “the best [something]” although “Adsense optimized” is kind of a vague term. How exactly is it “optimized”? Usually this means it just has lots of spaces for Adsense ad-shaped ad spots, but how was it determined that where the ad spots are is the “optimized” placement?
This might be a good idea, but it would be nice if you had data to back it up. I also see “SEO optimized” themes a lot, but it’s not clear how exactly they’re SEO optimized besides “clean code” (this seems subjective) and “fast loading” (they almost never are).