If you haven't yet, you should at least consider adding Lion's mane mushrooms to your stack. It's commonly available at chinese food markets and it's cheap. It boost something in your brain called BDNF other wise known as Brain-derived neurotrophic factor. As to why you'd want to do that, think human growth hormone for your brain:

BDNF acts on certain neurons of the central nervous system and the peripheral nervous system, helping to support the survival of existing neurons, and encourage the growth and differentiation of new neurons and synapses. In the brain, it is active in the hippocampus, cortex, and basal forebrain—areas vital to learning, memory, and higher thinking. It is also expressed in the retina, motor neurons, the kidneys, saliva, and the prostate.

BDNF itself is important for long-term memory. Although the vast majority of neurons in the mammalian brain are formed prenatally, parts of the adult brain retain the ability to grow new neurons from neural stem cells in a process known as neurogenesis. Neurotrophins are proteins that help to stimulate and control neurogenesis, BDNF being one of the most active. Mice born without the ability to make BDNF suffer developmental defects in the brain and sensory nervous system, and usually die soon after birth, suggesting that BDNF plays an important role in normal neural development. Other important neurotrophins structurally related to BDNF include NT-3, NT-4, and NGF.

https://en.wikipedia.org/wiki/Brain-derived_neurotrophic_factor