The Lightrifle is a very good weapon, versatile, if you know how to use it. The DMR is a bit better though, easier to use. Not a good thing.
Of the Covie primary weapons, the Carbine sucks, it is too weak. Useful finisher but why bother with that when you can have a killer weapon. The Storm Rifle is powerful up close, but lacks the range of, say, SAW, or even AR.
The Suppressor is very powerful up close, but has even less range than the Storm Rifle (IMO, hard to say in retrospect). Kinda forgiving though, due to the Suppressor's large magazine, the Storm Rifle can't shoot for long.
The BR is nearly as bad as the Carbine, it lacks the range and precision of the LightRifle and DMR. Beats the former in short-mid range, beats the latter if the BR user gets the first shot. EDIT the BR and DMR are both 5 shot kill weapons, the DMR has more zoom (as does the Lightrifle, the Lightrifle is 4 shot kill while zoomed).
The BR having both recoil (as neiglible as it is) and spread is overkill. Remove either one, buff the Carbine to 7sk (or increase its rate of fire) and the weapon balance will be considerably better.