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This hast discussed to death, you know?
(*shudders* another ghost of user interface past... )
Experience levels have been tried before and they have always failed and will always fail.
First of all, it's a hell to support. Have you ever worked on IT first level support? Even getting people trough "normal" configuration dialogs is a hell. Having multiple versions of configuration dialogs and trying to figure out, which version the user has active is so much, much, much worse.
The second issue is, that as soon someone doesn't find a configuration option for some exotic feature he would like the application to have, he (or she) will turn to the "Advanced" level. Noone ever uses the intermediate level configuration dialog.
Nautilus had such a thing years and years ago. It failed, is was removed. It's dead and burried, please leave it there; it's just where it belongs.