I'm about six foot eight and i put a smaller after market steering wheel on my mustang and i fit pretty well now but i will probably get some different seats as well so i can get a lil more space.
It really depends on my mood but most the time i have the sound up loud enough for any car near me to hear or at least feel the bass. I never have the sound up when I'm near my house though i don't want my subs and amp stolen again.