For a non stainless, I'm voting for 5160 as it is cheap, easy to heat treat and works quite well for what it is
Semi stainless, CPM 3V. Great toughness, holds an edge well and has better rust residence then 5160 or any other 10XX steel
Stainless, not sure as I don't have enough experience with different versions. I want to say AEB-L but haven't used any yet. S110V on the other hand I have. Great stain and rust residence. Holds an edge but hard to grind. A bit brittle too