** Using WeBWorK **

OK, great - thanks! That explains why the changes wouldn't save.
Of course now I'll have to remember to change the weights on all future sets, but this solves the problem. Edit: I tracked down the line I need to add to my course.conf to set the default to 2 :-)

I'd also like to see the features you suggest. All of these are possible on the LMS side, but then the homework grade mode is necessary, which, as I mentioned, some students find overly complicated.

I used homework grade mode last year for exactly this reason: I didn't want to count the review assignment, and I wanted to let them drop their lowest score. But I had enough tech support emails from students to convince me to switch to the course grade mode this time around.