The Pelican drops being completely random is awful. Idk why 343 decided to bring back the feature of random spawns from Halo 4, it was easily one of its less popular features. These should spawn in the exact same order and locations, at the exact same timestamps every time you play on a map.
You want the moment when the tank spawns to feel like a mid-game event? Make it ALWAYS happen at the 4-5 minute mark.
Have more Banished vehicles, like Wraiths, Ghosts, and Banshees, drop in on the map with the Banished turret, more UNSC vehicles drop in on the one with the UNSC bases, and have it be a mix on Fragmentation to fit the aesthetic theme of the maps.
Have the locations of weapon drop pods indicated when their drops are announced, so anyone can tell where they need to go and get a feel for the map’s weapon rotation. Record new dialogue or reuse power weapon spawn dialogue of the AI or Spartan Commander saying “Snipers incoming” or “Rocket drop inbound” to help players get a feel for what order of weapons get dropped each match as well.
When you load into a map, with enough experience, you should know exactly what kind of experience you are in for from the beginning. Able to memorize both the locations and the timestamps specific weapons or vehicles will be dropped in.