So the tricky part about how low you want to see Snuggie go is what it does to the rest of the cycle. With Neko, if her nadirs were in the 70's, she's stay under renal threshold. Above that, and she wouldn't. It's hard to pick a band of numbers you'd like to kitty to stay between, and dose to meet that. It will take some experimentation on your part to see what works for Snuggie. But definitely ECID. If you look at Amethyst's SS, she can stay really flat and blue.
The other thing you can play with now is size of dose changes. Only we typically change by 0.5 units at a time over 5 units, some cats are sensitive to small changes. Again, Neko was. You could try doing a 0.25 unit reduction and see what it does to Snuggie's nadirs. The other thing to keep in mind, there is more than one reason an acros dose needs can go down. If he was seeing glucose toxicity from the higher numbers, he could break through and need to go down a bit. The tumour could wane a bit. And once you start Cabergoline, you will have to be very conservative. Higher reduction points if following TR, extra large reductions, skipping doses, BCS (partial doses) are all tools you'll need in the toolkit to keep him safe. Maybe - ECID.