critique my setup -- weak link? best way to improve?

Seems most want to flaunt personal experiences rather than address the OP's question

when is not the case? Not only that, people sometimes just post links to what they are selling. Still, if you post a focused question, you will get a lot of useful advice 

Advice on what’s next?

stringreen suggested “just enjoy.” That’s the right answer for this question almost every time. If you’re pretty interested in an upgrade that will add to the enjoyment with the greatest bang for the buck, that’s where the interesting part starts.

I’m sure that I’ve moved through equipment in the last decade, sometimes without fully hearing what an individual piece was ultimately capable of offering. If it were my system, I might try a different speaker cable, just to find out whether I can hear that fine of a difference.

Or I might try a different pair of speakers, as in that case I should definitely be able to hear a difference. This might also be true with a phono pre, but imo this would be easier to hear once the speakers were swapped out.

All interesting inputs, I sold hi end audio for any yrs, and here it is

START with the source, get the best...(to your ears) source, then you have a reference to go by.....think of it this way, in football you have offense, defense, special teams, coaches, OC, special teams coaches, etc, the list is endless, where to start to improve the team.......the  OFFENSIVE LINE.... I am from The Boston area, and you can have all the Tom Bradys you want, anemic O LIne...he is toast, weird analogy to be sure but it fits.......Source 1st....we had a demo of turntables with the same cart thru a Naim Nait and $300 speakers, the difference was quite clear and that was to people who knew nothing about hifi.....source 1st.

You will get WAY more bang for the buck with a $500 Bluesound Node and an $11/mth Qobuz subscription than any turntable/cart/phono stage upgrade at 4 - 5 X the price.

Spend the rest on upgrading your speakers. The used market will serve you well, just buy from someone with a lot of 100% favorable reviews here or on USAM.

Then maybe upgrade the pre-amp with all the money you saved not buying vinyl.

Cables later, lots of choices, buy used or from small direct to consumer sources like Frank at Signal Cable.

Just my 2 cents, and FWIW I started 6 years ago with a Pro-Ject Carbon Debut and look where I ended up - fortunately I’m still married, unlike this guy

I am sorry, the audio “source” is analogous to the OL of a pro football team?