Turntable consultation

Hello friends, and thank you for help.

I would like to have your opinion regarding improving the SQ of my turntable. Since I haven't listen to other brands except mine, which is Pro-Ject RPM 9.1 with class A cartridge and Tube Box phono, I know its very good turntable & arm, but is it class A ?

And if I upgrade the tonearm to a better one like 9cc Evo or other models will improve SQ very much and no need spend on higher level turntable ?

Or if I upgrade to higher level turntable like Signature 10, or other brands like VPI Classic 3 . How much improvement will be ?

My main goal is: resolution, musical, neutrality, and no coloration.

I'm trying to understand what best way and is it worth to spend more money.

Thank you
At $6K there are many options. I've seen many fine tables (and some not-so-fine) but I don't know any of them well enough to recommend them over others. $6K is about the price of my Teres table, but it's not made any more so I won't recommend you try to buy one. ;-)

Try to see and play with as many tables as you can. A vinyl rig is a personal, hands-on device, not plug 'n' play at all. At this price point it's important that YOU understand the table's design philosophy and feel comfortable with it.

Read manufacturer's descriptions, online reviews and owner comments... but take them all with a grain of salt. You're not reading to find out which one is the "best" (they all are, obviously!). You're reading to find a table you understand and can be happy living with.

Some will recommend their own table because it's their own table and they love it (else they'd replace it). That doesn't mean you would.
I don't know if this will improve SQ but might worth asking, Is high quality speed controller will improve the sound of Pro-Ject RPM 9.1 instead the stock Speed Box SE ?
VPI have SDS controller .
Any thoughts or suggestions ?
A lot of folks seem to be enjoying the relatively new Phoenix Engineering controller - it's a fair bargain as well especially considering it is considerably more advanced than the SDS. K&K Audio also has a new controller out that looks intriguing as well.
My personal experience with an outboard speed controller is limited to my purchase of the Basis unit for a Basis Debut table. This is a quite expensive dual phase unit that required modification of the motor (two separate power feeds to the two-phase motor and removal of the phase splitting capacitor). The benefits of using this outboard supply is, to me, quite subtle. While the sound is better--a sense of a more "solid" sound--the improvement is not nearly as obvious as the much cheaper upgrade of buying the newer and better belt offered by Basis. The Basis table, being a premium unit with incredibly close tolerance machining, probably had reasonably good speed control so that only small improvements could be made anyway.

I would say that while a better power supply for the motor will probably improve sound, I would expect a low bang-for-the-buck return on such investment. The ability to change speeds without moving the belt is a convenience that could factor into the decision.
I would say your table is CLASS B. Spend your extra money on top models of the speaker brand you prefer. More advances in speakers in the last few years than tables