Tbh they need to half the carry capacity and lower the spawn rates (again, I know) of special ammo for PVP only. Secondaries should kill much faster than primaries, or there'd be no point to them. However, they're heavily abused because you have a select few who either camp at the spawn crates at the back of the map and load up on ammo (snipers) or they run around picking up ALL the map's crates (shotgun rushers). So you have a few ppl with a lot of ammo the entire match and the rest with none. If a sniper can only hold 5-6 shots and can only get more 2 times a match, there's be no more constant sniper lanes all match. If shotgunners only had 5-6 shells and could only refresh twice a match, they'd use their ammo more reactively than proactively, as they're intended to be used (BTW, Universal Remote completely goes against this philosophy that Bungie themselves have stated; as a primary, it let's someone constantly use a shotgun aggressively instead of reactively).