I have owned a Spacedeck w/heavy kit and Ace Space arm for 15+ years now. I have never given a thought to upgrading the arm or turntable and can't speak to how other arms compare to the Ace, but here is an older thread that may be of interest to you.
https://forum.audiogon.com/discussions/best-arm-for-a-nottingham-spacedeck?highlight=arm%2Bfor%2Bspa...
https://forum.audiogon.com/discussions/best-arm-for-a-nottingham-spacedeck?highlight=arm%2Bfor%2Bspa...

