boomtho: This is a hard one for me to answer. The first obvious solution is Ivan Rabb - we already know he's going to be great, but if he takes the next step to IVAN FREAKING RABB, it will create a lot of leverage and opportunities for the rest of the roster. If Rabb becomes an even better help defender, it'll allow Cal to play more smallball (with him at the 5) and cover up for some expected mistakes at the point of attack for new Cal players. On offense, if he adds a bit more of a face game up from the elbow, it'll allow Cuonzo to run more motion through him.
Besides Rabb, though, we need high-level contributions from a lot of players on the roster, even if only within their "lanes", to reach our ceiling. We need shooting from Mullins, Domingo, Bird, and hopefully Moore; we need more defensive solidity from Kam and King; we need robust perimeter defense from Mingo, Davis, and Mullins. Any of these factors can swing the direction of our season.
LeonPowe: I'd want to point out Jabari and Ivan as our two best and two most important players, but I don't think they are the biggest factors between a good and great season. I think it's how well Charlie Moore adapts to Div 1 hoops, how well Mullins fits in and if Domingo can turn it on. I think Bird and Rabb are proven commodities and any improvement we get from them is incremental. But if Moore can turn into the next Randle or Domingo can fly around there like Derrick McKey and Mullins can contribute like a next generation Richard Midgely - we'd really have something.
Reef: Charlie Moore. There's a wide range of outcomes for this team, dependent on a lot of players fitting into a new rotation. But if you take the view that defense is more or less a given, then the key to our ceiling is offense, and the key to developing an elite offense is finding a true point who can shoot, penetrate, and distribute. To be clear, I think Charlie is a year away from being that guy. But if he gets there by mid-season, we're looking at top 10. That's a pretty nice ceiling.
Nik Jam: Ivan Rabb is our star player who almost certainly will be leaving after this year. If he can exceed his play from last year, this team should be very very good.
Would also be great if Jabari Bird has a senior year for the ages. I can see it happening, especially if he can get a shot at redemption in the NCAA tournament.