On the topic of ex aura use, I personally have two uses for it. First, is the standard f4 ex aura in the corner to get hella frames and 50/50.
The other use is one I haven't seen mentioned yet: using it during a last round/"next touch wins"scramble. While it's not necessarily the best mindset to have, you will make your opponent have to work a little harder to kill you. you'll be able to take a few more stray hits, or make your opponent combo you a little longer should they catch you. This isn't exactly mind blowing tech or anything and in extremely low health scenarios it won't help much obviously, but I thought I'd share.