He looked pretty shaky in the cup games earlier in the season so it's not a big surprise he wasn't playing. He's certainly grown in to a better player this season. Nobody will be getting him for cut price fee, though. He won't be on big wages so there will be no need to offload him, like a Sissoko or Wijnaldum, so a low offer would be batted away.
If Rafa stays on, I think he'll bring in his own Captain asap. I appreciate, fans are looking for even the smallest of positives from the mess we're in, but, I don't get burdening Lascalles with the captaincy after a dozen or so games, particularly with the expectation that'll be their next season. Too early for me, let him grow as a player without any added pressure.
It always depends on the individual player. Some thrive with the responsibility whilst others fold. If Rafa stays I'll be happy with whoever he picks.