In autoduel, old game from the 1980s, you would grab a chassis, armor, engine, weapons, etc, and the game automatically calculates your speed, acceleration, turn rate, etc. Does that not work very well in an MMO?

actually not, it becomes hell to balance. :/ You tend to end up with very very singleminded setups and not much variation. Giving too much choice is sometimes worse than no choice at all.

please search around, it has been mentioned alot, usually with the term "modular"

i was searching with the term 'customize' or 'custom' or 'customizable'

Interstate '76 was a really good example of that (everything that AutoDuel aspired to, and more)