Mark, this might go without saying, but if you implement this, it'd be nice if it were just one menu entry instead of two. Like "Select power mode" with the options "normal, force AC, force DC" or something like that. I think the number of menu entries is getting a little crazy. Any chance you'll start breaking some of these options into submenus? I realize it's not the most important thing on your plate but scrolling through the long list of menu options some of which I never use gets to be tedious.
Actually I just looked and it's pretty easy to comment out hijack menu entries in the kernel source. Maybe I'll just do that.