I like consistency in layouts, so the above (to me, no offense) has no continuity or fluidity to it.
Even one of the layouts I'm working on now for a customer is themed very different, MAME themed after "Bubble Bobble" , NES "Mario & friends" , Sega "Sonic."
However each layout will use the same font and be branded "_________ Arcade."
I tired using the tree before, found the set up rather difficult.
I have my cabinet set up where left/right is used to navigate lists, and holding P1 button 1 + 1 player start allows me to switch to a different emulator.
I find it to be an easy transition and quite user friendly.