You will also want to make sure there is significant mechanical structure connection the outer c-channel to the inner c-channel. The way it is right now there is nothing keeping the c-channels from twisting which will create a lot of binding friction on all those shafts going through all of those bearing.
I’m just suggesting you guys adjust this but for the gears and wheels that connect, I’d recommend adding spacers to make it stronger, I’d also not use steel if I were u guys, also if you guys go 5 holes longer on the c channel, y’all will have enough room to have standoffs if front of the wheels to connect the c channels, that would protect the axel on the wheel from bending from contact as well as making the overall structure stronger
