Regen is just sent 5-12 volts up the regen wire on mine, which was the white wire. I'll just get my 5V from the hall supply or throttle supply, since I don't feel like opening that controller again.
I don't have a clue where an idea about regen being hard on tires came from, unless it was significantly strong regen resulting in a jerky result. With my speedier wound hubbies regen is smooth and soft, so it's a matter of getting used to how far before a stop to engage it and then add a touch of mechanical braking right at the end. Brake maintenance is now almost non-existent, my favorite part of regen. It's also a great safety feature going down hills. On very steep downhills continuous regen keeps speeds plenty slow. On grades less than -10% I have to do intermittent regen. I consistently get 8-10% regen recovery and even higher when I ride harder and faster, so that much more range.
To me regen is a must on any DD ebike. Sure it needs to be tuned properly, which may be difficult with a non-progammable controller. My Leo 36 is supposed to be set at regen force High, but if that end up too strong, but I found a jumper that connects next to my regen wire on that board which I'm hoping is to create high. If so then I can wire a switch in to give me regen high/low at the handlebars.
If that doesn't work, I'll try some other stuff. eg Another scooter controller had a wire described as regen high on the sticker, but I couldn't get regen to engage at all with that wire. I tried to ground and I tried to +5v, even +12 since it was a scooter controller. What I found was that interrupting the power to the halls is what activated regen, which may very well be what all sensored controllers do to make sure you don't even end up power and regen at the same time. That activated low force regen, and then that regen high wire connected to ground gave high force. While variable regen would be the ideal, low/high regen on command works very well.