Eduard/ExtraTech do the M36 and M10 Wolverine in 1/72 scale as does UM. UM also does the T1 Combat Car.
S-Model makes a lot of what you are looking for. They often come in 1+1 sets, with one being a full kit and the other being a wargaming kit with simpler builds.
As far as significant tank development, most of the later US light tank lines were dead ends, but the role of the ligh tank was absorbed by the armored personnel carrier, like the M113 and Bradley Fighting Vehicle. Much more important vehicles that are in use for well over 40 years while the entire lifespan of the US light tank was half that.
And just to shake things up, the Stryker MGS by Dragon and Trumpeter is another branch of US armor development.
The RPM kits are nor for the faint of heart, much like those by AER as well. They make lesser known subjects, but are of limited quality.
ACE Models is another company that makes limited run kits but also are of important vehicles.