Thanks for the suggestions, all
klr.b wrote in post #12378067
Do you have a plate right now? The problem with most plates is the channel for the head of the screw are milled just slightly larger than head itself so there's not enough room for the replacement you're envisioning. If there is enough space, you still have to deal with the height of the replacement screw. If the head is too high, the plate may not sit in the clamp. I'm assuming you mean something like
this
or
this
. If you know a machinist, it'd be a lot easier.
The links you provided--it's exactly like that. The plates I've got have plenty of room on the underside--should have no problems getting it to twist with those hooks attached. I might just have to find out how wide they are--if they're not TOO wide, getting a few of those would be the optimal solution. 
Worst case, I can take a grinder to the top or bottom of the screw, if there's a clearance issue.
jrscls wrote in post #12378718
The Benro B3 ballhead that I tried came with a universal plate that used a standard hex screw but also notched out so that you could tighten it with a coin if needed. It looks like it is available separately as part number PU-70. Maybe you could find a screw like this and use it on your existing plate.
Actually, I have two benro ballheads with the notching you refer to. It's common to have a coin handy (either a Nickel or Quarter to be exact), but that's not always the case. I'm willing to pay extra to not have to worry about always having a hex wrench or coin handy. One less thing to think about.
Now that is a very unique solution. The additional weight wouldn't bother me, but that does appear to be a bit of additional bulk... How does it handle? Do you smack yourself regularly with the clamp tightener, etc? This would appear to be the most elegant solution overall--no need to even remove the QR plate from the camera or lens collar!!