A really nice summary! Thanks for creating and sharing it to this community.
I don't know if you want to include it in your list, but..
a good gambler knows the math
Knowing exactly how to increase / decrease bets on certain multipliers as well as recognizing patterns & calculating potential profits or losses in real-time will help you avoiding irrational decisions.
But it is almost impossible to know the math of a game if you are new into it. That is why it only applies to well and know gamblers in here. Not all the gamblers know this.
And i know a bunch of them that do not even know what they are playing, they just care about the profit.