Sand box , bring back armor lock but with a better twist one u active it when he punches the flore to active the armor lock every thing close to it get sends upwards to the sky not a huge lunch like the repulsor but a bit higher than and normal jump but it should not affet big vehicles .
Bring back halo 4 shield hability the drop shield is 95% useles love the it has a counter if you shoot the base but the shield it selft is suoer weak if u make it stronger it would make more sence to pick it up …
Bring back halo reach jetpack u can make it as good as apex legends valkyrie character but with the og halo reach feel where u could shoot mid air .
Bring back hR evade with a less travel distance but with a recovery to shoot from it and less ending lag
Bring back HR holograms but with a better mechanic instead of trowing only one you could make it 2 with and shield effect of like 20% of HP to fake out oponents
Bring back h3 hp regeneration the green gaget the gave u shield it would change how u play strongholds and Koth
Others games where inspire and took things out of halo games
Like apex 80% they got inspire by halo
Mirages holos from halo reach
New catles shield halo 4
Gibby bubble shield halo 3
Horizon lift halo 3 gravity lift
And more and more …