Effective ways to upgrade a Music Hall MMF 2.2


I am researching ways to upgrade a Music Hall MMF 2.2 and would like to get some advice.

1. Change the platter to an acrylic one.
2. Add a Soundbox - this is intended to be for automating changing the speed from 33 to 45 with a click - why are folks indicating this would improve sound quality? Confused about that aspect.
3. Changing the cartridge - how high can I go for this type of turntable and arm? Will get a different counter weight if required.
4. Should I consider changing the arm? When do these things become ineffective? I.e., what role does the table itself play in the quality of the sound?
5. I would like to upgrade my phono stage from the NAD PP2 that I have. Would a Project Tube Box make a difference?

Thoughts welcome.
shugho
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The most effective way to upgrade most tables, including ones in the price range of the 2.2, is to upgrade the cartridge. Take a look at your table in the Needle Doctor website and yu will find some upgrade recommendations. I recently upgraded my Pro-Ject table with a new and better cartridge and switched to an acrylic platter at the same time. Much better. Best of luck.
Thank you for your advice. It all makes sense. I was also thinking that buying a new cartridge that I can later transfer to a new turntable makes a lot of sense. Also, the mat and the acrylic platter sound like reasonable upgrades that will provide the right ROI. I will let you know how things go. Thanks again.
Best advice is Viridian and the Nagoka MP-150 .
ALL any sensible person would ever need.
Which leaves me out .
Schubert, Sorry - what is a Viridian? I am not finding it in my web searches. That is the second recommendation for a Nagaoka MP 150 which intrigues me. I was considering a Ortofon 2M Blue or a Denon DL-110 based upon advice from a dealer and this is in the same price range - do you think it is a better cartridge than these or just different?