Now, this whole post is in relation to the amount of Heavy Ammo we get in Destiny 1. There are three main Heavy weapon types; Rocket Launchers, Machine Guns and Swords. We're going to disregard Swords simply because they aren't used enough to warrant a complaint. But, the amount of ammo a Rocket Launcher gets versus the amount of ammo a Machine Gun gets is ridiculous. There's no logic. The amount of ammo each gets should be the "same" i.e they should each get enough ammo to kill the same amount of people, not accounting for splash damage for Rocket Launchers or body shots/missed shots for Machine Guns. Right now, Rocket Launchers get 2-3 rockets from a single Heavy Ammo crate meaning they can kill 2-3 people at minimum (again, without accounting for splash damage). But Machine Guns, they can kill 5+ people from a single Heavy Ammo crate (with accounting for missed shots or body shots). It's kinda annoying, tbh. I hope, for Destiny 2, Bungie takes this into consideration. If you made it this far, thank you. TL;DR: Machine Guns can kill more people from a single Heavy Ammo crate than a Rocket Launcher can. It's not that fun.
Machine guns won't be in Destiny 2, Shotguns, Snipers, Rockets, Grenade Launchers and Fusions are your power weapons. A rocket will most likely have 1-2 rounds and 3 the most. But as it going for shotguns and etc. you'll have more ammo, everything balances out, but for things like trials and or Elimination, not sure how those will play off. It's a wait and see.