Assuming you already have speakers you are generally comfortable with, I would not recommend that you screw around with the OEM design and OEM crossovers…especially as a tweak.
There is no “set” or “standard” crossover point - different speakers mean bespoke different crossover points.They are already “tuned” at a certain precise point with their bespoke speaker drivers and parts. What you are proposing is to introduce an unknown new component on an informal ad hoc basis that ignores the speaker’s overall design characteristics…. This can - ….and usually will… - be a recipe for a bad outcome.
“ if it ain’t broke, don’t fix it “ rules.
Your are better off to consider other alternatives if your audio presentation is lacking.The philosophy is clear. An affordable speaker (… which includes yours left in its full OEM current state …) matched with a high-end source and amplification makes more sense than an expensive speaker with a cheap amp and source.