I'd wager that most agency devs have wanted to do this too. CMS's never work the way you want them to as an dev.

Thankfully, the work you have done (along with your competitors) in making headless CMS's viable not just for devs but also for content maintainers has made CMS work far more enjoyable.

It's awesome that you not only built out the dream most agency devs have, but made a successful business out of it at the same time.