Im on DHEA only and Ive noticed improvements in my health too. It seems hormones are a major part of the immune system.
One thing I dont see you using is methylation support. Methylation is responsible for making glutathione(immune function), hormones, neurotransmitters, and detox.
Try adding TMG to your supplements to speed up the immune system and detox pathways.
Make sure your not too heavy metal toxic with copper, mercury or other metals also because brain fog will never go away if your metal toxic.