I have rebuilt Xovers many times each capacitor sounds different
foils are normally better then typical poly sprayed particle conductors
go to humble homemade hifi capacitor test
Duelunds copper foil oiled paper being the finest ,and can take up to 4-500 hours or more to fully runin ,, resistors path Audio are far better-then the typical ceramic type.sonically and accuracy , inductors copper foil for tweeters midrange are far better then these cheap sledge hammer wire over a iron core ,for bass a big awg 12 or 14 guage open copper core are preferred , all these parts are much more expensive but dramatically increase imaging soundstaging and musicality.
as far as drivers absolutely mechanically the surrounds have to loosen up the wire has to stabilize as well as other mechanical parts of the drivers ,I give it at least 200 hours playing at increased volume levels , I use Isotek excellent runin cd ,and track 3 tune up track for years. I have over 20 years at this and owned a Audio store for a decade.