Yes, you would get better sound with a dedicated phono preamp rather than the Music Hall built-in pre. But to make a significant upgrade in sonics, I would suggest a better TT, cart and Phono Stage. It would cost under $1000 and the improvement could be huge. There are some package deals online.
I'm sure that you can get some suggestions from others more informed or maybe look thru the archives or needledoctor dot com.
I'm sure that you can get some suggestions from others more informed or maybe look thru the archives or needledoctor dot com.