This is my idea for a balanced H5 sandbox (or for any future Halo game, for that matter). Sandbox is made so that each weapon is just as useful in its own special way. Some weapons are omitted to avoid redundancy, or for the sake of keeping balance. If you have any criticisms or suggestions, explain your reasoning please. Please tell me what you guys like and/or dislike about my ideas 
Magnum
Silenced variant. Extremely hard to hear. Has a slower rate of fire (not spammy like Reach or H4âs pistol). Would be good for stealth and as a sidearm, but not much else.
Assault Rifle
Would perform like Halo Reachâs AR. Slower bloom expansion rate but less damage. It would be geared towards beginners. Easy to use but isnât very effective overall. However, it does come with a headshot multiplier.
Battle Rifle
Would be more like H2âs BR with tight spread, slower rate of fire, and more geared toward medium range (the BR from H4 was more or less designed for close range).
Shotgun
Like the Shotgun from H4, but with a more consistent pellet spread. The pellets would be arranged in a ring-like pattern thatâd loosen up over distance, so itâd be a bit harder to hit with.
Sniper Rifle
Similar to its H2 counterpart, except the reticule would disappear when unscoped. Still same accuracy, just no reticule to make the Shotgun more useful for skilled players at close range.
Railgun
Just like it was in H4, but without the massive bullet magnetism and aim assist.
Chaingun
Replacement for the SAW. Similar damage and firing rate, it just has to spin up for a brief moment before firing, and it would also reduce your movement speed whenever the barrel is spinning or firing (but not when youâre just carrying the weapon around). It would also have extra recoil and feature a single endless magazine (not unlimited ammo), rather than using multiple seperate clips. These changes would restrict the weapon into a support/covering fire role, to better balance it among your everyday automatics. Lastly it would also have similar accuracy to the AR.
Frag Grenade
The usefulness of Reachâs grenades with the grenade indicators from Halo 4, to make them a bit less âcheapâ.
Plasma Pistol
Slower rate of fire, higher accuracy and damage per shot.
Plasma Rifle
Performs exactly like it did in CE with the stun and accuracy intact. The only change is that itâs firing rate would start out fairly slow, but it would accelerate over time, eventually firing as fast as the Brute Plasma Rifle.
Carbine
Closer range oriented. Wayyy higher rate of fire to increase the skill gap with the weapon, with less damage and more spread to compensate.
Needler
Ripped from Halo 4.
Energy Sword
Performs just like it did in H3. Little to no changes
Focus Rifle
Redesign. Think of the Quake 3 Lightning Gun. The beam sways when you turn around while firing, you must try to aim with your movement to compensate. It would have low damage per second, but very high push force.
Concussion Rifle
Redesign. Heavier arc, more damage, slower rate of fire. It would be designed for firing over obstacles that block your aim. Yes, itâd be situational, but that would make it more useful if you remember how crappy it was in H4.
Plasma Grenade
Like Halo: Reach, but with grenade indicators.
Laser
Promethean blaster pistol. Slower projectile speed and higher damage than you might expect. Harder to hit with but very rewarding for higher skilled players who can lead their shots. Firing at the ground while jumping would boost you very high into the air (âLaser Jumpingâ). It would also have enough push force to easily screw over an airbourne player. Has a charged firing mode that acts as a flamethrower, lighting up surfaces and damaging players over time.
Light Rifle
Like it is from Halo 4. Designed for longer ranges.
Suppressor
Redesign. Plays like a carbon copy of the SMG, with higher recoil and spread than the AR, but a faster TTK and a larger magazine size.
Scattershot
Redesigned to function like a double barrel slug shotgun. It fires two slug like projectiles at once, that spread apart over longer ranges. The projectiles would bounce off walls with consistent accuracy, and it would take two shots (four slugs) to kill a fully shielded enemy.
Incineration Cannon
Redesign. Fires one large molten ball of magma (or whatever that red stuff is), releasing a huge shockwave upon impact that either kills enemies or strips away their shields. It has very limited ammo, and has a slow projectile speed that makes it fairly dodgeable (if the player has good enough reflex). Good for launching assaults against multiple enemies at once.
Flash Grenade
Stuns players, blurs vision, and deafens hearing. It doesnât detonate instantly, but is very, very useful.