Ok, so I'm just a beginner and this is a very crude design idea, so don't spend too much time on it.
Imho, a lot of treadle hammer designs I've seen are flawed in 2 ways - the weight is brought down by the foot through the linkage - so your foot feels the hit as it bottoms out, and the springs just bring the weight back up, fighting against the blow the whole way and adding nothing to the falling weight. I then saw this video, specifically the time shown, and I had a silly thought - why push down when the spring and weight are doing the work? If stomping on the treadle did the opposite, raising the head, enough whip could create quite an effective beater - hence the "backwards" treadle (I really don't know what to call things). Maybe it'd spring too much and be a one hit machine, but one assisted hit is better than none.
For this to work, you'd need to set it up so the weight is suspended by the spring off the anvil, but still has plenty of travel to give it a good bash. But you're no longer fighting lifting springs and there wouldn't be a direct shock to your feet. You could design it with an overhead spring or like the video linked, but I'd like to think a Little Giant or Champion spring design with the weight on a slide could work better. And down the road, it might even be able to be motorized without a full redesign or too much stress on the components.
I'm sure it's not anything new and someone here can tell me why it won't work, but I've been thinking about it for 3 days now, haven't come across anything like it, and am just short of setting about building it just to try it out.