For "local" flavor, they should really get Bob Fitzgerald and Jim Barnett, the Warriors' announcers. Both are local to 2K (just as Damon Bruce is) and it would be easy to get them in studio. They're also considered one of the best local broadcast teams by Simmons and Lowe in their Watchability ratings.
Bob Fitzgerald has already done announcer work as Bob Steel for one of the NFL2K games, so he'd fit right back in. His commentary in real life is also pretty predictable -- he'll pretty much look at the biggest stat category difference most games and pronounce "THAT'S THE DIFFERENCE IN THE GAME!" like a major revelation, so programming his commentary to sound authentic would be pretty easy.
Most people are impressed with Barnett even if they aren't Warriors fans-- he's very knowledgeable and doesn't sound like a complete homer. He sounds a *little* bit more old school (he loves to say "what a nice, nice young man") but that would be a good change of pace from the current "national" sounding group. I wonder if he's not "hip" enough for the social media crowd 2K might want to appeal to but for authentic basketball fans, he's great. He's also retiring after this year
so he should have a bit more free time.
They can also go with Tom Tolbert over Barnett, who's also pretty entertaining and will likely take over Barnett's spot next year.
In terms of TNT guys, I think EJ would do a good job with the sort of delivery Damon Bruce gives for the halftime show, who I think is already very good. Barkley and Shaq will get old quick as they pretty much just mumble inanities and most of the fun is not knowing what (dumb thing) they'll say next and playing off each other. These guys aren't going to be nearly as much fun reading from a script, and you'll get the uninspired delivery that Jalen Rose gave for Live. Off the cuff guys just don't work that well in a video game and will get stale faster than anyone else. If 2K gets the TNT license and wants authenticity by including them for flavor, fine, but no way should the halftime commentary be built around Shaq and Barkley.
I find Reggie Miller boring but C-Webb would be great both as a second analyst for the halftime show or the third color guy next to Harlan and Kerr. Kenny would be okay next to someone like EJ. Anyway, you need guys that sound good giving soundbites no matter what the context. That's why the current team works so well. The stories and tidbits never really sound out of place while they fill up dead air.
Either way, getting Miller and Webber does have one major benefit-- it means we'll probably get them in game, and they get to make comments about themselves. Who would turn down an opportunity like that?