Acctually there were energy weapons in the vaults... Did you skip the G.O.A.T young man?!
But would it be a viable skill to choose?
At most there would be like 2 weapons, laser pistol (civilian issue), home-made flamethrower and maybe... Juuuust maybe... A laser rifle.
I just don't see it as a viable skill to be taken if it's going to take place inside a Vault.
It's not like the Vault is going to have miniguns and plasma casters in them yknow.
Just basic guard weapons, scrap weapons and home-made weapons.
So what the hell, let's just skip Guns as well and just have all three (Explosives, EW, Guns) in one skill: Firearms.
A skill solely dedicated to this DLC. (Or any upcoming DLC which takes place in a role besides the Courier.
Would make more sense since the DLC isn't meant to have the PC reach lvl 30 anyway.