I'm in a similar, but less extreme boat. The new interface has its perks, especially in terms of discoverability, but for tasks that need to be done repeatedly (request 10 beds be made before you have a manager, for example), you really miss the ability to rock some chords.
It took me some time to remap the muscle memory but it felt so worth it. The Steam version is not just a new AI, it introduced a lot of gameplay changes which really improved the underlying systems a lot.
The version available for free on their website is the same exact program as the one you purchase on Steam. It simply includes a different set of graphics for the UI. These graphics are designed to look as if they are made up of text characters, but in reality they are still just sprites. The sprites that come with the version you buy from Steam are designed to look like a normal but stylized gui.