Both laser rifles & plasma rifles should have a way higher DAM than they currently have in the game. Consider that in real life, Nd-YAG lasers are used to cut metals, and the beam of a laser rifle in FO is more powerful than the Nd-YAG. And plasma just burns through everything, that's why it is encapsulated into a very high magnetic field in tokamaks.
In my opinion, energy weapons should be way more powerful, but also much more difficult to find (I got attacked by Powder gangers in the NCRCF wielding plasma pistols, for instance).