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
#3 and #5

Upgrade the cart and phono pre.

Many choices out there and I'm not sure about your budget.

My advice, Ortofon 2M Red/Bellari VP130 tube MM phono
pre for about $350.00 all together will bring new life to your 2.2

Money to spare, DV10x5/DV P-75 (used) for about $800.00

Again, many options out there, just my opinion.
Agree with Viridian's advice. The NAD is a solid performer and works well with your table--when you upgrade a component like that you risk having it expose weaknesses in the turntable/arm that might ultimately lessen your enjoyment. I would not change an arm or a platter on a table like this, unless, in the case of the latter, you want a different sound (acrylic, in my experience, might sound a little less lively, and if you want that the mat might be the cost-effective way to go). Just my $.02.
Shugo, for the acoustic music I listen to the MP-150 is better.
If rock is your main fare an Ortofon Red is all you need.
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LOL - my apologies for the snafu. I was not paying attention to the names of posters.