Ok, so this plugin would be pretty simple.. basically it'd chain together multiple actions into a single menu item or hot key. Since I use both masstagger and replaygain on my files, I could have them run with a single button, saving me work I'm sure there's countless other possibilities as well.

Now the tricky part would be getting it to confirm each plugin's respective dialog box. I don't know if this would even be possible without some major changes in plugin architecture, but a a TAGZ-based conditional system that configures each plugin appropriately would be pretty damn cool.

No, it wouldn't.

I didn't think so... still, the first part should still be feasible, right? I don't mind having to hit ok on a few dialog boxes, I just think it'd simplify things somewhat.

I recommend Autohotkey. You can set it up to do pretty much anything if you can be bothered learning it.

I have used it to do what you describe - perform mulitple Foobar actions from one hotkey. Basically, you use one AHK hotkey to trigger several Foo hotkeys.

Cheers.