What do I need to sacrifice to get a .5 or +1 increase in turn or inertia + for Ambassador?

Zen? Sure
EC? Nice!
Dilithium? OK
Extra module? Not a problem!

With the advanced Science options even a .5 in turn would really go a long way.
Will the Dev-gods listen???

Seriously, even if the Devs upped the turn of Ambassador even .5 if would really, really be a nice ship (still inferior to Excelsior) of course, but it would make the difference much less noticeable.