Thanks for your review. Regarding uninstallation, did you see our uninstallation instructions here so it can remove all Joomla patch files, components, modules and plugins:
Also, could you please point out how bad is the backend? Were you using the latest version? Although we are not designers, we have tried to make the backend look as nice as possible. You can see how new version looks like in these two videos:
Regarding the "poorly executed website", our website is not perfect, but we are trying to provide as much information as possible for users in our wiki website and creating video instructions for users.
Finally, did you ask for help from our Support Desk? If you have asked us this question, we should have provided the answer for you on how to uninstall the software completely.
Anyway, hope the above information helps all Joomla users.