This is really interesting Hope to see more of this printer! I kinda did my own calculation in my country, and man..i gotta say I kinda want to build it now. Soon!
A "version" with aluminium extrusion would not be a version, it would be a totally different printer and would have to be designed from scratch. If that's what you want to build, checkout the Voron 0. Having said that, I do have a "concept" version with sides made out of carbon fiber.