Update: I got Hori gamepad today. Pretty nice. Different than the Ave 6, but I like both.
Anyway, so I realized the pad has three settings for slow mo: off, mid, and high. I retapped those connectors and routed them to: start, select, and button three. The switch maps start, select, or normal button 3... into button 3. This means if you put "select" in there, you can set button 3 rapid fire and get rapid select (this is funny to do in Air Zonk!). Same for start -> rapid start or "slow mo". So I didn't actually lose slow-mo; it's now just a button to be pressed held. The mod works regardless of which mode the gamepad is in; 2 or 6 button mode.
I've never had a 3 button pad before with Turbo and PCE games. Holy crap does Bloody Wolf play differently. Great for Soldier Blade: switching between high/low speed for the ship is so much easier. Of course, I tried Forgotten Worlds out with it. The SNES design with 3button support feels pretty comfortable with that game in Ave 3 mode. Though I kinda wish the pod would rotate a bit faster.
All in all, love the gamepad and love this mod.