Just a sidenote:

Average neuron density within that brain hardware.

There is no strictly linear correlation between neuron density and brain power:

An impressive abstract showcasing synaptic pruning:

The aim of this study was to quantify the total number of neurons and glial cells in the mediodorsal nucleus of the thalamus (MD) of 8 newborn human brains, in comparison to 8 adult human brains. (...) In the case of the adults, the total number of neurons in the entire MD was an average of 41% lower than in the newborn (...).