I spent a bunch of time getting WordPress into a state where I could run it headless and then just a short while after I decide to switch over to Ghost anyway because it just ended up feeling like the slicker solution I guess. There were some things that annoyed me with the WordPress setup to be fair, chief among them the fact that all the images hosted there were getting copied over on each deploy which felt very wasteful even if it wasn't time I spent actively waiting for the task to complete since it was done automatically in the background and Ghost seemed to have the more straightforward integrations to get the images hosted on some other platform so that they didn't need to be part of the deploy process.
Beyond that, the writing process is largely similar, if perhaps a bit cleaner of a default editing view in Ghost than WordPress though that is easily enough configurable for it to not really be that big of a difference. The separation of the admin/publishing side and the published website itself is also more clear in Ghost, which means setting up the whole thing for headless operation was considerably smoother than it was with WordPress which somehow makes me trust the whole thing a bit more even if I personally didn't run into any problems with WordPress or the setup really. To be fair, I am now slightly less reliant on any sort of plugins which is a boon in itself, since while they are one of the greatest strengths of WordPress they are also the source of many of its problems which makes me a tad more confident that the current setup will be easier to maintain than the previous one if only marginally.
This change of backend however, has also had me thinking about potentially changing the frontend as well, since one of the primary reasons I went with Eleventy originally was the fact that I could copy over the images from the backend during the deploy but as that is no longer necessary with them hosted off-site I might end up using one of the other static site generators I looked into but discarded due to them lacking this functionality. I'm especially curious about this since during my experimentation Gridsome and to a lesser degree Nuxt really caught my eye since I have had some previous experience building sites with Vue and being able to bring that familiarity in to this as well would be a nice bonus, along with their rendering fanciness really contributing to making the site actually feel a bit snappier which to me is one of the main points of using a headless instead of traditional CMS in the first place.
That project is still ongoing however, so I'll have to update the state of it at a later date if I actually do end up switching, since to be fair for the most part Eleventy is doing its job in a nice and quick manner and there is no real need to switch—though I am ever the tinkerer, never quite satisified with every detail and always curious to test new things so that probably ends up being the primary reason I decide to test something different in the future.