Welcome to the nut house. On screens, expect a lot of opinions. I put a V-Stream on mine after considering all the choices. Plenty tall enough with room to spare for my 6-nothing.
On tank bags, I run a small First Gear Silverstone bag with a clear window on top. It can be either strapped or magnetic, as it comes with both options. I run it with the magnets. I've got a bigger First Gear Laguna tank bag for long trips.