Really cool concept of drumming with your feet while playing another instrument.
I think it would be really cool to experiment with different trigger sounds. The muscles in your foot severely limits the nuances available to play, and trying to imitate the sounds of a regular drum-set will not go over well.
I think it is possible to achieve much cooler playing, if you skip the idea of your pedals needing to imitate a drum-set entirely. Experiment with some 808 bass, electric kicks, etc.
Combining that with your great piano playing would create an entirely new feel of music, whereas it can easily end up sounding like a good pianist struggling to cooperate with a much worse drummer
If you look at the video where I'm playing piano I'm using electronic drum sounds, though I still want to play around and figure out ones I like better.
Here's what this is eventually going to fit with: https://www.jefftk.com/p/rhythm-stage-setup-v3
To me, slightly raising or lowering the hi-hat is an essential dimension of playing, and double strokes / buzz strokes / rolls are important too, so drumming with only feet seems very limited. And why anyway? It's not so hard to find other people to play with. What I really want is for someone to figure out a hi-hat you can play standing up.
I really like the feel of playing in a small group, where you can be in very tight coordination with someone else. I currently play, or at least I do when there's no pandemic on, in a duo and a trio. In either of these, adding another person to be a drummer would radically change the feeling of the group.
Additionally, everyone you add to the group makes the logistics of booking more difficult, and makes organizers less interested in booking you since you become more expensive.
In foot percussion (clogging, tap, podorythmie) people traditionally use both their heel and their toe. A heel strike and toe strike make different noises, and you can play faster by using them both. When I started looking at electronic foot percussion ( 2013) I assumed I would use my heel and toe, and that was how my first versions worked ( youtube). I had serious trouble with vibration isolation, however, especially when playing live, and after a few gigs I switched to only playing with my heels.
Similarly, if you look at a standard drum kit, a foot only does one thing at once. Traditionally, one foot is on the bass pedal and one is on the hi-hat pedal, and perhaps you might move your foot to a different pedal sometimes, but you don't have one pedal for your toe and one for your heel.
This is not a limitation of acoustic playing: Drum-tec makes a bass drum double pedal with heel-toe operation:
(DP-921FB)
With electronic drums, this should be even more practical, but I still don't see anyone doing this. Well, almost no one:
(youtube)
Mezerg plays his kick drum with his left foot and snare with his left heel, by putting his foot diagonally across the two pedals. Similarly, sometimes he plays two different pedals with his right foot as well. Each, individually:
He's playing electronic dance music, and he's playing a live version of a drum machine. He has each of these elements, and he brings them in and out over time. Here's what it sounds like with everything in: @t=21:36.Kick on the downbeat, left toe: @t=17:31
Hi-hat on the upbeat: right heel: @t=5:08
Snare on two and four: left heel@t=20:21
Something with the right toe: @t=4:27
Very occasionally he plays other things (@t=9:51) but it seems like that is mostly not his style?
I've been trying heel-and-toe drumming, and while I'm not very good at it yet, I do like it. I've been using my left heel for the kick and left toe for the snare, right toe for the hi-hat and right heel for a crash or another hi-hat. I've only been doing this for a few days, so these examples are not very good yet, but I think they illustrate what is possible:
(youtube)
(youtube)
(youtube)