I've played with the front springs quite a bit a 200#/in. is the best compromise I've found. Yes they are a tad stiff for road use but you haven't seen my roads either
Right now the car weighs 2050lbs./930kg with a full tank, full interior, and a big stereo.
I've done the fuel injection thing before but I want more power, reliability and mileage, 3 things that air cooled motors aren't renowned for. Now I have built up one hell of a good motor for it, and got 2 of 3 but I really want a bit more from it.