Let's save cross coupling for later. It's a great next step but it is a bit of a can of worms.
Two things to accomplish before tuning this topology.
Make sure that each loop RT and high frequency reduction is identical.
Keep the modulation moving. Just simplify the design and use a standard chorus on each tap. This is just an artifact of your implementation. There is nothing wrong with that. Work with something between 10 and 50 samples per second. And split the chorus phases exactly into 40 degrees between each tap.
If it sounds a bit to chorused, well that can be randomized better when you go to the 56k, for now just call it a feature!
What you have now is the topology of the EMT 250. If you have access to an IR set of the 250 then you have something to tune against.
I encourage you to tune your current design until you can beat the 250 IRs. To be fair, vocal and snare would be the most useful comparisons, as these are where the 250 is most often used.
The thing that will seperate this topology from the others is the snare reverb will have a tail that sounds like "cawhhhh" and not "chchshssssss". The next steps will change this, and this is a downside!
In the next step we will look at ways to further eliminate the tape loop sounds. But for now, the tuning steps I mentioned will help the tape loop problem and the left right balance. Adjust the tap gains/slope to help in both of these issues as well.
-Casey