He also kept the idea of having a flowing circle for mana accumulation at his hands and feet. So he added them again and also extended pathways to the fingers and toes.
When Eldrian wanted to start on the head he found himself struggling to keep everything as is. The network wasn't extremely complex, mostly just simple geometrical shapes to connect the mana 'strings'. But it was becoming too much.
So, to end it off, Eldrian decided to simply have the mana flow to his head in a circle. With pathways connecting it on all sides. He had no idea what it would do, he simply wanted the flow of mana to fill his entire body. Not select areas.