Solid work
@Lizerd. I like what you got. There is only one thing I'd change.
Speed
Base walking speed is 30 feet. Climb 30 feet (while not directly stated, as saurus live in a jungle it’s reasonable to assume they could climb trees)
I would remove the 30 foot climb movement rate since that doesn't mean "good at climbing" that translates to "as good as a monkey or squirrel at climbing." That means Saurus can climb as fast they can run. That also means Saurus can take 10 on climb checks, and run while climbing.
I would replace the "30 foot climbing speed" with "+2 on climbing checks." That gives them a substantial edge over humans, but it doesn't let them keep pace with spiderman.
Skinks probably should have a swimming movement rate. That doesn't mean Saurui can't swim. It just means Skinks can swim circles around them.
Maybe I'd make Saurus have a bit more extreme ability adjustments
+2 Strength, +2 Constitution, -2 Intelligence, -2 Wisdom, -2 Charisma
Plus all the other stuff you said. I think this would be fairly powerful but not so powerful that Saurus would need a level adjustment.
Skinks I'd give them -2 Constitution, +2 Dexterity, 11+ base armor save, 40 foot land movement, 30 foot water movement rate