I've been reading about improvements users have suggested and your concern that they may confuse or make things less simple for the majority of the users. I have a suggestion that may address that.
I found a feature of firefox for advanced configuration when I was trying to make the Addin window popup larger. If you type about:config in the address bar in firefox it brings up a web page with a warning symbol that states
This might void your warranty!
Changing these advanced settings can be harmful to the stability, security, and performance of this application. You shuod only continue if you are sure of what you are doing.
Then there is a button below this warning labeled "I'll be careful, I promise!"
You could do something similar to this and perhaps also have a button labeled "Reset to Default Settings" In case someone who did not know what they were doing changed some configuration settings.
If you wanted to be even more secure against novice users accidentally advanced settings which would end up confusing them you could force the user to enter a some password or do something like firefox does using "about:config" which is in effect a hidden password (you have to know what your doing to get to this page in the first place.)
Doing something like this might give the best of the best of both worlds - simplicity for the majority of the users and advanced options for more experienced users.
To keep support issues down you could state on the "Warning page" that these advanced features are not guaranteed to work. This way if an advanced option some how got broken an advanced user could still use the software it would just take more time like it does at present.
Hope this suggestion may be usefull. It would be great to have some great advanced features. Doing this might allow addition of more advanced features without complicating the things for the majority of users and keep your risks down with adding new code.
I have attached a screen shot of the about:config page firefox has implemented.
That's actually a good idea. I was thinking about the same thing.
The only problem is hot figure which setting is for advanced users, and what is for the rest of the world.
But this is the way we should go, I completely agree with you.