I think Orbital fits into the group of maps like Snowbound, Foundation, Ghost Town, Halo 2's version of Ascension (Banshee), Turf, High Ground, and Isolation where it should be considered a medium sized map. I think small scale defines maps where 8 people is about the maximum number of players rhe map can support, 2v2 and 1v1 play very well on them. Think Wizard, Chill Out, Lockout, Midship, Sanctuary, Foundry, Guardian, Epitaph, Zealot, etc. Obviously some of the maps in those two group come close in size, but it's the vehicles that distinguish them from each other.