I'm okay with the idea in principle. In execution it works like this:
level one extended mag + fight = certain death
level two extended mag + fight = empty gun before your first down
option one: hide until weapon is recharged (at which point your squadmates have either died or won and there's nothing left for you to do either way)
option two: quit
level three extended mag + fight = you'll live, may even get a down or two, but will still run dry before the engagement is over - unless your squadmates are gorillas.
level crazy **bleep** new mega extended mag = just keep shooting, you'll never run out. Basically just free unlimited ammo, and some other perks I don't even remember or care about. So over-powered as to be laughable.
So that's the energy weapon change. Feast or famine. But mostly famine. If I had to guess I'd say that the tuning was done exclusively with master tier players in mind. If you have an aimbot then how much ammo do you really need? The rest of us, on the other hand, either need to be prepared to sit out half to two thirds of every fight, or find new guns. Unfortunately for me the tripletake IS the new gun - the one I switched to when the charge rifle was removed from the game. Now I'm too old, too tired, too impatient to switch again. I've tried the scout, the 30-30, etc. Useless. I've switched to the longbow during seasons where the tripletake went into a care package, and I was willing to tolerate it because it was temporary. These new shenanigans? Here to stay is my guess. Maybe they'll re-tune so a normal player can still use energy guns, but I'm not hopeful.