I'd say your list depends on just why you own guns.
These are what I'd consider the Bare Minimum:
If you are a prepper?
1) A semi-auto, magazine fed rifle, such as an AK-47, AR-15, M1A, Mini-14, etc,
2) A concealable pistol of your choice
3) OPTIONAL: A good bolt action rifle in .223 or .308.
Preferably 2 of each (one is none, 2 is one).
If you are a hunter?
1) A bolt or lever action in a decent big game cartridge (.30-30, .308, .30-06, etc).
2) A .22lr, preferably a rifle of some kind
3) 12 gauge shotgun, preferably pump action
With those three you can take any game animal without much trouble, and the pump gun can double for HD.
Just interested in self-defense?
1) a concealable pistol
2) a long gun of some kind, such as a shotgun, a pistol-caliber carbine in the same caliber as your carry gun, or a semi-auto such as an AR-15, Mini-14, M1A, etc.