Dan,
I'd agree that moving APM and user admin to the subsite admin page would make sense (obviously, don't show them to people who don't have site-wide admin).
A little less baby-step-ish, I'd really like us to have one /admin control panel acting as your portal into all the administrative functions that you have on the site (or in this subsite, if you're under /somesubsite/admin).
/Lars