i would love to think that there are hidden values such as aerodynamics (probably unlikely) and weight (likelier and i hope they are there) that aren't made known
As a matter of fact, there are!
Each ship features about 20 different stats that are responsible for its handling. Like weight, corning, grip, turn, roll, turning rate, turning deceleration, speed, acceleration, ... Therefore, a ship's visible stats are a representation of those hidden stats that physically belong together, thus are grouped and totalized (averaged, accumulated or interval-based, that I don't know) in a single number.
That's why ships with same stats in, say, handling (like the mentioned Assegai and Harimau), don't actually handle the same.
For reference see Colin Berry's statement in this thread (I highlighted the important terms for you )

I hope I could "shed some more light" on that topic for you.