If you look around I think you will find one or two maybe that might build you a Lebowski controller. Iirc there have been some posts about that somewhere here. Don't know what kind of power you are aiming for, and I don't know what is possible with the lebowski controller but it seems people are raging about it so my guess is it will scale up well to fit your need if you got someone to build it.
On a side note I've heard good things about controllers from http://accelerated-systems.com. They got ebikes controllers all the way up to powerful motorcycle controllers, with a new powerful mc controller being released Q1 2018.
I think the accelerated system is the guys behind the controllers from ebikes.ca, iirc they are even involved in the phaserunner controller from ebikes.ca. So I am sure they know their stuff.
If you are power hungry take a look at their e-motorcycle line. Notice that the rated power is continuous power. Meaning peak power will be radically higher, see the spec sheets. Notice the peak A. That is a good indicator that these controllers will not hold back when you twist the throttle.
http://accelerated-systems.com/products/escooters-emotorcycles/