There's currently a control panel for web hosts called 'CyberPanel' which is being developed by the community, and it's fully open source with zero paid Addons or licensing costs.
I've enquired with them and there's no plans to make it paid, and community feedback is taken seriously, and feedback is constantly taken on board.
Recently they made a website preview (like cPanel has) for people to use before nameservers prorogation and I've suggested feedback such as changing the login page name and they are planning to do so.
It might not be ready yet, and I'm not a huge fan of the design, it's going to be very strong competitor for cPanel in the future, as it's completely free.
Design wise, it's a modern design based loosely on the metro theme that windows has, it's great for clients. But for resellers and admins, it isn't very user friendlly and it's not hugely customisable.
We will see what the future brings, in a couple years time it could start to replace cPanel.
If my hosting business was fully built on VPS servers, I'd certainly use something like CyberPanel for my free hosting, as it has the features clients need and it heavily saves on costs.
I believe it also has a built in script installer, I've not heard anything about a website builder, but no doubt they'll partner with one in future.
Once they have theme documentation, lots of developers will begin to make cool themes, hopefully more than cPanel did. Maybe someone will even make a cPanel design copy, I don't know.
I've seen people copy the old cPanel design before and put it in their own control panel, so I don't see why not.
Anyways, if anyone wants to checkout CyberPanel, you can download the latest version (Currently 1.5) at https://CyberPanel.net
If you have any thoughts regarding CyberPanel or other freeware, please tag me (if HD allows that), so I can read your responses and pass on feedback where needed.