I disagree, this is a completely dumb idea and should never be considered. There is no outcome where this is a good course of action, and (in my plays) you never have enough Pokemon on the bench to even consider swinging for the attack. Also, if possible, please refer to an ‘all-out’ as a Hail Mary, as YOLO is a completely unneeded acronym and should not be taken seriously.
Yes, because running Virizion-EX means attaching Grass energy and allows an even easier time if you’re playing a Flareon variant (Of Night March) whereas running other stage 1s is, yes, more difficult to set up and have deck space for, but (personally) I would celebrate if I ran into a Mega Rayquaza-EX deck with Virizion-EX as a variant. Flareon/Raichu would allow a very quick match, and it wouldn’t be in their favor.
I believe Mr. Mime is absolutely vital as every single Pokemon in your deck consists of low-HP (yes, even your precious Mew-EX with a low 120 HP), which means Landorus-EX can ram through two Pokemon a turn. You’re not helping the cause by saying Revive. I would opt to run different cards in my build if there was space.