Did he actually use a fake name for the room? Not his high-roller status tied to his real name?
And he did use gloves.
But the gloves could have been because he knew he'd be holding hot barrels, plus to handle all that pounding of a lot of rounds with his hands that weren't likely used to it.
Surely, he couldn't have taken all the guns away, and he must have known they'd easily be tied to him.
Of course he couldn't have removed all the guns. Gloves just make sense, from the standpoint of handling hot weapons--wouldn't want to burn his fingers, especially if he is going to blow his brains out anyway. See? It isn't what we would call "rational".
The rest, not so much, either--including shooting up a music festival crowd, for that matter.
As for getting away, that requires first getting away from the crime scene. The rest becomes another episode of America's Most Wanted, looking for some country that won't extradite.
$100K seems like a lot to some folks, and it is here for most people, but in some foreign countries, it is a king's ransom.
Money can buy credentials, people do that all the time. It can get you far on the lam, and the guy is a pilot, with multiple residences and three aircraft we know of. Deep pockets can easily buy the illusion that someone can do that which is unlikely, and that impression is reinforced daily on television and in the movies.
I can't speak to the guy's mental state, and there may have been something organic going on there, too, but at some point I think he thought he could get away. Obviously, he didn't think of everything--especially the smoke alarm--which just means his long term plans were poor or nonexistent.