@jdaviescoates, thanks for the shout-out. I'd been meaning to hop over here and let people know about Co-op Cloud, but you beat me to it! 
(Writing here in my personal capacity as a Co-op Cloud hacker, not speaking for Autonomic or for the project)
I'm personally really grateful that Cloudron exists, and the Cloudron team has been super-supportive to Autonomic over the years. Again, not speaking for the coöp, but I don't think we're fixin' to stop using Cloudron completely 
You're absolutely right that the licence change was a huge factor in motivating me to help make Co-op Cloud, though – I'm proud that Autonomic had otherwise strictly avoided using proprietary software for our own infrastructure, and I share your sadness that we're maybe reinventing a wheel when there's such a great option available already 
That said, it's totally Cloudron's prerogative to re-license, and I wish them every continued success with the closed model 
@fbartels, I think you're absolutely right that Cloudron is intended for a different group of people than Co-op Cloud is: I think Cloudron will continue to be a better "hands off" option, especially for people who don't know or don't like the command-line 
To me, the main exciting things about Co-op Cloud are being able to keep your configuration in version control, using docker-compose (i.e. multi-service) format instead of Dockerfile format to package apps, and the licence. I guess, as @marcusquinn is saying, that there'll be many people who'll be more interested in the ease-of-use and automation of Cloudron, than that stuff.
@fbartels I'd also agree with you about what Co-op Cloud is:
a deployment utility for docker swarm along with a standardised way of deployment.
I'd just add that, as well as those two things, it's a collection of 30+ applications packaged using that format https://docs.cloud.autonomic.zone/apps/
Lastly, @scooke, that's a really good point about where the data is stored:
It's interesting to me that their user-initiated installation all takes place on and from the local machine, not the server. That actually worries me because if my laptop dies, and I haven't made that most recent backup, what happens to my server setup?
Co-op Cloud has a (so-far-undocumented) feature to mitigate this: you can store the ~/.abra/servers/ directory which contains app definitions in version control, or even symlink to folders in different repositories, if you have maintain different sets of apps with different servers with different teams. I use this myself and it works great, with minimal risk of losing work if my computer blows up.
A next step would be to auto-deploy the apps based on changes to repositories, which is something I'd like to add in time for the beta.
One other alternative (also not yet documented), which I'm also using on one project, is that you can install and run Co-op Cloud on the VPS you're managing – in which case the app definitions live on the server just as you're saying.
Caprover is definitely pretty similar: I'd started a comparison between it and Co-op Cloud but it doesn't look like it's made it into the docs yet. Watch this space! 