The only trouble with Mika's ascent this season, when he averaged 20.3 points and 9.2 rebounds as a sophomore, is it makes the team's performance seem more disappointing. If you had told me Mika would be this productive in his first season back from a church mission, I would have upgraded my preseason forecast.
I didn't predict an NCAA Tournament bid for the Cougars, believing it would take a year for the team to come together (similar to Utah's situation). That basically proved true during BYU's 22-12 season that ended with a loss to UT Arlington in the NIT's first round. The premise was that everybody would stick around and the Cougars would figure out some things next season and make an NCAA appearance.
That seems doubtful without Mika — just because he's that good. He looks like a second-round draft choice in June, which would be a sufficient opportunity to launch his NBA career. With new rules further connecting NBA rosters to NBA Development League affiliates, players such as Mika and former BYU teammate Kyle Collinsworth will have more opportunity to improve within a system.
The same may be true of Kuzma, although I see Mika's game as more advanced at this stage. Selfishly, I hope they both end up staying in school for another year. Fans deserve to watch the best possible product on the court. The good part is that whatever decisions they make will have stemmed from good information.
The two best things the NBA has done in my lifetime are establish a rookie wage scale that basically eliminates contract holdouts and give players the chance to work out for teams in May without committing themselves to the draft.
Mika and Kuzma owe it themselves to see what the NBA thinks of them then decide where they go from here. If they leave, they will have left some things undone in their college programs, but that's their choice.