You're right about that. A lot of the units that were added in Civ IV to make stack vs city combat interesting filled (or created) niches that are no longer necessary with 1upt. Without stacks you don't really need +city defense, +city attack, or anti-melee specialists anymore. So the choices can seem a little more natural: spearmen should probably still have a bonus against mounted units, but crossbowmen can just be medieval ranged units instead of an anti-melee counter, and swordsmen can finally stand proud without worrying about bronze-age apes with axes.
There are certainly fewer unit types, though. I hope thay they make up for it by providing more region-specific graphics for them. I've already seen two different Spearman models (that don't appear to correspond to Civ-Unique units).