it would really be cool if there was an Autoadd ++ nodes button I could push.

You can add Javascript code to your FreeNodelet, which will be run on each page view.

Have it figure out that you're on a voting page (I guess by looking for the CSS class of the radio buttons).

Add a hook into the "vote" button so that it collects all the "checked" radio buttons' corresponding nodeIDs into a list and do something useful with it (probably involving AJAX).

I've done something similar recently (with bart's help) to enable selective "quoting" of the parent post when replying to a node.

-David