Since I always thought the default Houdini theme feels pretty outdated I spent some time to make it a bit less clunky. A lot of the UI is semi-hardcoded so not everything was customizable, but I still think it's an improvement.
It's a little darker, takes away a lot of the gradients and hopefully makes it all feel a bit more uniform and easy to use. I've used it for a while now and I personally really like it, so maybe someone else would appreciate it too.
The whole process of making a theme is pretty chaotic since a lot of the UI styling isn't really organized, so if you find some elements that look off please send me a note!