I have the first one. It’s very good. An alternative if you don’t like dust: Silverstone MM01B.
A bit overkill for two cards, but one of the best PSUs ever made.
Yes.
Blower & FE cards: no, it will stay cool. Open-air cards: possibly (I’d say: much probably) it will get hot.
It may be the case to opt for a gen4 ssd and ECC ram. All the other stuff seems to be quite OK 