Factory undercoating removal

I have done 2 cars and it is a difficult miserable job.Looks nice when done but the car is echoey
and "tinny" sounding. Going to try something different on my current project.
Going to detail everything back to factory finish but leave the undercoating on. Just clean, touch it
up where necessary and paint it factory semi gloss.
Hoping the car is quieter and nicer to drive when done.