They need
-Falcons as a dropship and hornets to counter the banshee
-A new covenant dropship to counter the falcon
-Locusts to counter the mantis (if they keep it in)
-Revenants or spectres to counter warthogs
I like the way you think...
Maybe you could go on a recon mission with Jun or have to clear an area with a team of ODSTs, including the Rookie Who is now a squad leader or meet Thel 'Vadem on sanghelios to repel attacking storm covenant ships.
Just some thoughts.
Maybe you could invest in customizing your warthog like armor in reach, instead of the K/D ratio.
Then you could have it dropped as ordinance once a game but if its destroyed you have to wait for it to be fixed off-screen
What about an armor ability for elites, where you holster your weapon, activate your plasma blades(used by elites for assassinations in reach) and sprint around for a certain amount of time.kind of like a rage/berserk mode.