If we somehow did this, I feel as if Baynes would come back for cheap without a doubt. He's made some good money, and with 2 rings I feel like he would want more. He's also 31, so doubt he gets a big offer.
I'd try and keep the extended core together, including Smart, but wouldn't at all be surprised if a team offered him big money (assuming he plays a pivotal role in this hypothetical championship run). If he does leave, I'd try and trade into the second round and pick either Jevon Carter or Keenan Evans, as I feel like they could both be acceptable bench guards in the NBA in the long run.
Other than that, I just run it out. Pick BPA with our #30 pick, don't make any drastic changes, and let this dynasty run its course