Ok, I do have one question before giving a full answer because in my experience I use different soaps for different purposes. What is your intended use with the foam gun? Pre soak / LSP stripping / bucket wash replacement?
Normal pre soak: Meg's GC works well as do most normal bucket washes that foam well in a bucket. I dont suggest any wash and wax soaps though. My personal soaps for this are DP xtreme foam, CG maxi suds, CG honeydew, Meg's hyper wash. You really should try one of the foam gun soaps to see what the full potential is. I wouldn't waste my money on the gloss enhances like CG Glossworkz as you are pre soaking and are going to wash everything off. So it is a waste of an expensive soap IMO.
LSP stripping: I use an apc mixed in my normal foam soap or CG CW&G or CW&C. These are made to strip LSP at the right dilution ratio.
Bucket wash replacement: I use any of my normal soaps. The more it foams in the bucket the more it foams in the gun.
I hope this helps.