I hope he gets vigoursly fisted in prison by people wearing 50mm Invictas.

Both watches are essentially equal in wearability (I.e. size, dress up/down) and are inverted in the sense of their symmetry (I.e. horizontal plane subdials on the up/down vs vertical on the moonhpase) but have the same “busyness” in that sense to me. I think either you could easily dress up or down with a change of the strap, they are both gold "dress’ watches, but that doesn’t mean they aren’t suitable for everyday wear! I wear my dress watches with everything, only person who will care is you lol.

The up/down seems to add a bit more diversity to your collection being a manual wind (the winding of a Lange is one of the nicest winds out there) and you’ve said it yourself you like the dial layout better and movement display. Seems like you’re leaning towards that model already so go with your gut.

More than likely BB pro hands etc., will not be compatible with a 16570 (or similar). Centre pinion will be different, torque to move the hands will be different, etc. Really not worth the effort to most likely have it not work anyway.

I’d suggest trying the BB pro on bracelet as it keeps the weight strapped down more and has a nice microadjustment to get the perfect fit.

For 15k or less you’d be in a price point to get a vintage sub with a matte dial - lot of character and would fit your criteria.