Leonpoi: d100 takes more time unless you're like me and have several d100s
(actual 100-sided dice -- they used to make them) or use a computer program.
Like you, I also used a "point blank" range that is half of short range, where your chances of hitting are doubled, and in autofire, each bullet hit on a 1-3 on the d6.
I didn't like the 3 rounds = 1 shot of V1, though I really didn't like the vehicle combat rules. It could take 2 or 3 minutes to resolve one hit against a vehicle, and when you were designing new vehicles, you were often educated-guessing as to where the components of the vehicle were.