Personally for me, I’d rather have these weapons make up the majority of the Halo 5 sandbox:
http://halofanon.wikia.com/wiki/Halo:Combat_Evolved(NU)
Plus my Cryoshot idea to serve as a secondary CQC weapon (shotgun that fires slow-moving ice crystals in a tight spread, requires target leading but slows down movement, and can freeze the target for several seconds if you land most of the projectiles on the target), and my Vortex Cannon idea as a super-weapon (similar to the BFG9000 in Doom, but the explosion generates a black hole that stays on the map for a short period, which can deal light damage via shockwaves that emit from the center and suck players in who get too close). This would make for an excellent core sandbox with 12 weapons (excluding the grenades), as long as they’re all equally as useful and interesting as one another, there is no need to add the extra, unnecessary fluff.
I personally believe that they need to minimize the amount of weapons for design/balance. Cramming in a bunch of fluff (just for the sake of having it) isn’t a really good decision, it causes the game to be too unbalanced, confusing, and cluttered. Why not just go with a smaller set of weapons for the core sandbox, so they receive more attention and are all made to be balanced alongside each other, as well as equally useful in their own special way. “Less is more” is a very true statement when it comes to the first-person shooter genre as a whole. I don’t mind if they add a couple of extra weapons for custom games and forge at the last second, but the “fluff” weapons should not be integrated within the core gameplay, and should only be added in after they’re finished perfecting the core weapons. Honestly, I really find the Halo series as a whole to be awful at balancing (so many examples I can list), so I feel this aspect should be top priority to improve the competitive aspect of gameplay. The game would be far more intriguing and strategic if they designed each weapon to be good in their own specific situation and more or less equally as useful as one another, rather than simply grabbing than overpowered weapon and mindlessly blasting away with it.
Vehicles should be first-person so it’s balanced alongside vehicle combat. In BTB for example, if you’re a smart player, you’re always going to wanna be in a vehicle if you have the chance. By increasing the skill gap for vehicle usage by making it so players need better situational awareness, I believe gameplay would be overall better this way. I also think Halo 4’s vehicle damage resistance needs to be kept. People say they were too weak, no way. They were very effective, they just weren’t overpowered. A classic Warthog would make you almost invincible against infantry unless someone carried a Spartan Laser, now you’re actually a bit more vulnerable. It’s necessary that you need added damage resistance when entering a vehicle, but to become almost unkillable by infantry is definitely going overboard. Forgive me for complimenting Halo 4 on something, that game was a piece of trash, but I’m the kind of person who will give credit where credit is due. I think they should have the Warthog, Mongoose, Falcon, Scorpion, Ghost, Revenant, Banshee, and Wraith as the returning vehicles, but with the additions of the Siege Bike (with somewhat more realistic motorcycle physics than the Chopper had to offer) and the Light Assault VTOL (make it an aerial counterpart to the mongoose, better for transport and getaways, but crappy for combat). I also feel the Mantis should return, but ONLY as a one-map thing like the Elephant was in Halo 3, otherwise it would dominate the entire BTB playlist.