-Plasma Rifles and Laser Rifles are statted as low-level weapons, which would be fine if you could get them at a relatively early point in the game, but you don't. You get initial access to energy weapons at the same time you get access to the (far more powerful) better guns.
Untrue. The Yangtze Memorial has a grave that ALWAYS has a random energy rifle in it, so you can easily get either a plasma or laser rifle as soon as you exit Doc Mitchell's House.
Use the Plasma Caster or don't even bother, essentially.
Even the Plasma Caster has issues. It decays super-quick and it's almost impossible to find outside of the one that's located in the Silver Rush. Gun Runners almost never sell it (even if they did, it would be expensive as [censored]), and neither do the Van Graffs. Brotherhood of Steel might, but since you typically have to kill them to advance the plot, that hardly matters.
The Tesla-Beaton Prototype (or any Tesla Cannon) would be godly if not for the fact that it eats ammo like crazy (40 for cannon, 45 for Beaton) and is even harder to repair than the Plasma Caster because Tesla Cannons are even rarer.
So is there gonna be a modder who could volunteer to balance energy weapons like giving better damage rebalancing the ammo consumption and such?
That's only half the problem, really. The other side of it is that there's a serious lack of variety for energy weapons compared to most other weapon choices. The way it's set up, you go from pistols, to rifles, to heavy weapons, so if you're a fan of either pistols or rifles, or if you have low STR, you're JWF at endgame.