Fantastic infomation here, sorry to necro this but i had a kind of strange use case that i would love some advice on related to this.
Im thinking about a implementation where the screen space widgets would not be able to collide over each other (think big loot drops in path of exile or diablo when you hold ALT). From what i understand this method would not be best as i would not be able to get that kind of control. Would i be best writing something within a AHUD and avoid UMG to get that kind of control? at the moment seems like the best idea but would be open to other implementation hints (i may be missing something with all these new features).