Experimenting with speaker pairings?

Has anyone played around with pairing different speaker combinations in a recording setting? This is something I love experimenting with in guitar cabinets and wanted to try out with bass cabs as well.

Specifically, I am looking for a recommendation of a 10" speaker that may pair well with or complement an Eminence BP102 in a ported 2x10 with tweeter. This is solely for purposes of recording.

Parts list:
Driver 1 Eminence BP102
Crossover Eminence PXB:3K5 High pass crossover
(note: the crossover will high pass to the tweeter but the drivers will run full range)
L-pad Eminence PX-LPAD
Tweeter Eminence BGH25-8
Plug and Play Jack to allow the drivers to be used independently or together

My one thought was that maybe a speaker that is a little darker would be a good choice since the plug and play jack gives the flexibility to run any combination of drivers and/or tweeter. The BP102 is pretty well balanced so I'm thinking that may end up as my main front and center sound. The tweeter will be to tweak my highs and maybe the other driver could add a different character in the lows.

Cabinet = Port City 2x10
Bass = Rick and/or P Bass, using a plectrum.
Amp(s): B15N, SVT CL, Verellen
Mic(s): U47fet, U87, AKG C12VR, Yamaha Subkick, AKG D20, SM7B
Mic'ing typically done between 6" and 2-3'
Style(s) are in the rock arena but range from pop-rock/alternative to metal.
The mic'ed bass cab gets paired with a DI that goes Big Trees -> REDDI -> Fearn.
 
If two drivers share the same chamber they need to match. Otherwise the stronger driver will dominate the weaker driver...worse case scenario both drivers are destroyed.

There are a few exceptions that have been made over the years...but not many. An example is the old Mesa PH1000 which combined four 10s and a 15 in the same box.

Also, with bass you can't just drop random drivers into a box and guarantee good results. You have to consider how the box is tuned and whether the tuning will work with the driver. If the box is not tuned properly, sound quality, low frequency response, and power handling may be poor.