What I don't like is the almost identical weapons. In some regards 343 took this to an extreme, in other cases they did try to give weapons they're own area of expertise. Take the grenades for example. They all work pretty well overall but each has it's own "perfect fit". The frag grenade is the jack of trades but master of none. It can be used in any game type or map, but it's best suited for games like rumble pit. Where you have large groups and you want maximum carnage. However it's not so great in BTB, with open area and lots of vehicles. This is where the plasma grenade really shines. Then there's the Pulse grenade, which is probably my favorite. But it's use is very limited. It often doesn't kill a player, it does however block an area. So it's fantastic in small objective based maps/games.

In some ways, 343i tried and succeeded in making places for items/weapons to fail and succeed. The Plasma pistol and bolt shot are two other good examples. Each has a role. But then in other places such as DMR, BR, Carbine, Light Rifle, AR, Forerunner AR, Covie AR (the fact that I can't remember their names proves this point even more), it feel like 343i lost their inspiration or they couldn't figure out how to make the weapons similar but different aside from the look and sound.

Bungie, is not beyond make weapons bland either. In Halo CE the Plasma Rifle had a nifty little ability of slowing player movement and turn speed. You could shoot the player and circle around behind them for an easy old school assassination. But after the first game it lost this ability, thus making it no longer unique.

In not a game developer, I haven't been hired by Bungie or 343i because I have the many talents and skills that they all do. They all have done a much better job than I could ever hope to, but it does FEEL like some of the weapons could use a little more inspiration or uniqueness rather than a range/damage/RoF boost or reduction.