A front bar promotes understeer. A rear bar promotes oversteer.
I've got a 19 mm (3/4") bar on both ends and it's just too much on the front, even for somebody who wants to hoon their car. The big bar makes the car harsh and makes the front push more than I'd like. I need to soften it up - I'm not sure how much, but more than it is. I've pulled some small leaves from the front beam, with no noticeable difference in ride quality, but less spring means that less bar is needed as well. The stock VW beetle bar is 12 mm (.47"), so that's quite a bit softer. There is a middle ground here - the 181 "Thing" had a 15 mm (.59") swaybar, which is available new from CSP/Kerscher. To be clear, I'm not advocating for anything - I've done nothing here. I'm still running the 19 mm (3/4") bar on the front and I still don't care for the ride or the handling.
I've got no issues in the back with the 19 mm (3/4") bar- no tendency to kick out or become "tail happy". I do wonder (a lot) how the rear will behave if the front is softer.
There is an orthodoxy regarding what we think works with beam suspension cars that doesn't really work very well. I applaud Randy for coloring outside the lines. What he's done may work out, or it may have some flaw he hasn't seen yet. At least he's doing something to make his car better.
He does like the changes he's made so far, and that can't be discounted.