If you got it working to meet your needs, then it is designed to be flexible to the extent you need. There are possible and likely scenarios, even when the entire site is built with the utmost efficiency, where several access levels could be required. Something maybe like a business site that has several locations, and each location may have different levels of access for manager, assistant manager and so forth. So SA is made for more complex structures.
The most I've needed so far is two levels of admins and regular user logged in. Plus, I've used the CMS that comes with Site Sculptor which automatically configures the different access levels. content management.
I totally understand about the effort it takes to get something working right and if it works, leave it be. With each new project, you'll find a way to do something better than the last one, it's sort of a never ending learning process.
One of the first sites I built was a training program that contained a 50 question exam at the end. Each exam question was a separate page, containing the question and choices with radio buttons. The radio button with a value of 1 was the correct answer, so the response of either 0 or 1 was written to the database and the final score calculated at the end.
The next time I built an exam, I used a single page, but populated the question and choices from a database table, much more efficient. But i don't think I would have figured this out without doing it the other way first. I needed to go through the process and make it work as best I knew how at the time before I could start seeing other possible solutions.
