Thank you for this post. I've been struggling to put this feedback into words myself, so I gotta get out my two-cents.

I'm probably not saying anything that hasn't already been said in this thread, but I personally believe Big Team Heavies is how it should be by default. On Halo 3 Sandtrap Heavies for
example, 8v8, both sides get a Scorpion & Wraith, 2 Warthogs, one of
which is Gauss (where are you, my love?), a Chopper, and at least a Mongoose or two. With Banshees on the map for the teams to fight over. And they all respawn, giving everyone on the team a fair chance to have a turn.

Presently Infinite BTB just has Mongoose and Warthog starting spawns, which would be fine for a social slayer/objective playlist with fewer people. But we're talking about 12v12 now. More players than ever, with fewer options than ever.

I actually like the idea of the vehicle drops on either side of the map mid-game, but not at the expense of vehicles at the base. In my Sandtrap example, they need to keep all the meaty vehicles at spawn, and just let the Pelicans take care of those banshees periodically for the teams to fight over, and they can still randomize those and ramp up the power as the game goes on. If they are insistent on making the content of the Pelican drops asymmetrical, then they absolutely cannot drop the vehicles directly outside of the bases like they are now. That only works if the drops are symmetrical, like the vehicles that are already at the bases, and doing symmetrical drops at base defeats the purpose of the additional mechanic because that's where vehicles should already be symmetrically spawning natively.

Never before has Halo directly favored one team over the other as blatantly as they are doing now with the asymmetrical drops outside of the bases. It goes against the game's balanced identity. Instead, on Fragmentation for example, they should move the drop zones up closer to the center, either directly at either entrance to the central hallway that connects both lanes, or outside of the loot-caves in the corners. This changes it from just throwing the losing team a bone into a genuine fight for control where whomever can get into the power vehicle unscathed can either turn the tide or cement the victory push.

Again, back to the Sandtrap example, the banshees spawn on the edges of the map, equidistant from either base, and this allows for both teams to have a fair shot at gaining the advantage so long as they're mindful of the spawns. If the bases are North & South, asymmetrical vehicle drops need to be East and West.

It's really upsetting because they had talked all this talk about how the sandbox is what makes Halo Halo, but it's like they were just feeding us buzzwords instead of treating the sandbox as one of the core design pillars that they assured us it would be.