I found Sakai, at least in the "T-Square" rebranding used at Georgia Tech, pretty annoying also (as of a few years ago), but at least it isn't sucking millions of dollars from their budget. At the time (possibly now fixed?) it had a very strong single-session assumption that would cause weird things to happen if you did obvious tabbed-browsing things like opening multiple users' assignments in new tabs. The "solution" was big red warnings at the top of every page about how you shouldn't do that.