i've had 8x10s 2x15s etc. honestly they don't sound that much different. 10 12 15 doesn't matter. you can eq your amp to make it sound how you want it to sound. i can get the same sound from a 1x15 as i can get out of an 8x10 cabinet. i think a lot of the sound is just in people's heads so to speak. they think a maple neck sounds so much different than a rosewood and so forth. 10s different than 15s or 12s etc. etc. there may be slight differences but it's nothing you or anyone else is gonna notice when playing live or when recording honestly. now different types of basses with different pickups and different amps give different sounds of course.
it basically comes down to what you want. i remember playing through an svt cl with 8x10 cabinet. we played a gig and i didn't have my amp so they had a GK rb800 or something that had 1x15 and 2x10s. it sounded pretty much the same as my svt setup did. exactly 100% the same? no but close enough. in the mix you don't hear all the tiny differences you hear when just sitting in a room playing by yourself. also coming out the PA never sounds exactly the same as it does coming out of your amp. post eq and direct out and everything. it still always sounds slightly different.
i mean think about it. when you play a gig the bass is coming out of a subwoofer that is 15" or 18" in the PA system not a 10" or 12" speaker.
having said that i like low end so i would make a 4x10" cabinet
some of the "different" sound comes from the brand of speakers used and how the cabinet is built. i remember trying the ampeg 2x15 cab when i bought my svt. their 2x15 cab didn't sound anywhere near as good as their 8x10 cab did so i went with the 8x10. however the mesa boogie 2x15 cab sounded just as good as the ampeg 8x10.