There are many inexpensive manual boost controllers with questionable results, and there are several aftermarket electronic boost controllers that are way over priced. I plan on making an electronic boost controller that is in the middle of these two ranges - with some extra features. Its currently comprised of an ATMEGA328p running the Arduino bootloader, a 4 digit 7-segment display, and a IRLZ44N to control the 12V boost solenoid. Will have simple and tunable PID control(probably only PD needed).
There are leftover analog inputs for things like throttle position, switches for different engine settings, or just tunable knobs in the vehicle.