I find the existing approaches for a thumb or finger controlled analog remote control too sensitive. At every wave or bump i vary the power unintended and have to concentrate finding the right power setting for the situation again.
The analog finger control is a challenge to waterproof and the designs i have seen look bulky and huge. Why not use a kind of up and down buttons which can easily be waterproofed for controlling the speed in steps and a dead man switch, which has to be held all the time, if released the motor stops directly.
Three steps would be too rough, 10 steps would be sufficient from my point of view.
Is there such a control available, is it compatible with our ESCs or bluetooth or maybe VESC?