Okay, first off what a f'n clean Coupe!!! I am a little biased as you will see below.
Just me but you might want to look at the H&R Super Sport springs and some Bilsteins vs the other springs and dampers you mentioned. I ran the Super Sports and Tokico Illumina's on my 93 Coupe for about 8 years and it was amazing on handling and rode very well. It was my daily driver like this for about 5 years then I was lucky to change jobs and get a company car. This is what it looked like with that setup back in 2002.
I would go with the MM subframe connectors of the two you mentioned however I run Global West subframe connectors on both my cars. Reason is they install to the outside of the front subframe which keeps the ground clearance. I also run the Griggs Racing upper subframes but they are by no means necessary.
Why do you want to run the 31 spline axles? I have 28 spline Mosers with a 331 that makes 370ish rwhp on Nitto drag radials and have zero issues. Only mention this as you will need to get a 31 spline carrier as well so it can get expensive for what you are gaining and may not need.
I would also so a basic tune up on it if that has not already been done (plugs, cap rotor, plug wires, fuel filter, etc.) You would be amazed how people don't change a fuel filter until the car won't run.
Again, great car and have fun with the build!!!