I wouldn't know how the Halo 2 maps are because I never owned the original xbox. My whole thing with the map selection is that from an on-foot standpoint, there are very few small maps.
I'm a Halo 3 guy, so I'll speak in terms of that. Here's how I'd judge the map selection after the first map pack (which is where we are now in Halo 4):
Small-Medium maps: 9
(Construct, Epitaph, Guardian, Isolation, Narrows, Snowbound, The Pit, Foundry, Cold Storage)
Large maps: 6
(High Ground, Last Resort, Sandtrap, Valhalla, Rat's Nest, Standoff)
In comparison to Halo 4:
Small-Medium maps: 6
(Abandon, Adrift, Complex, Haven, Solace, Harvest)
Large maps: 7
(Exile, Longbow, Meltdown, Ragnarok, Vortex, Shatter, Wreckage)
That being said, I do believe that 343 designed the large Halo 4 maps poorly from a vehicle-usage perspective. The only map with large open spaces are Ragnarok, (a remake) and arguably Vortex. But the fact remains that there are still many big maps that kind of suck for infantry gameplay.
EDIT: Ah, it would seem you detracted your disagreement about my map size ratios before I even finished typing this. Oh well. xD
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