I recollect @Belassi mentioning the versatility of Glucamate VLT thickener for such systems, search this forum and I am sure you would have something valuable on your hand.
Glucamate VLT is a superb thickener, it has great long-flow sensorials and also improves preservative performance. However it is rather expensive. Adding 1% cocamide MEA allows reduction of the thickener percentage and further improves foam.