That's not how it works. If Nonito Donaire will pick his opponents, the promoter and organizers will have to agree with it too.
If he's just cherry-picking easy opponents, that's not worth watching and promoters will think that's not a good fight to organize.
Donaire should just agree to whoever opponents he will face. At the point of this career, there should be no picking or selecting who he wants as he's starting from the bottom bracket now. Besides, I think he won't have a big problem facing top boxers in Flyweight or Super Flyweight Division that's why no need to be picky of his opponents in that division.
As for cherry picking, it will still be a hit for his match as everyone is waiting for his retrieval from the last lost that he has made. I'm sure that many fans of him will still watch whether it's from the organizer or his pick.
I guess there is no need for Donaire to do some cherry picking in the said division because I bet he can manage just fine even the champions in that division, he chose to fight in super-flyweight next so that means that he is confident enough that he can defeat those guys. He really knew that he cannot defeat the current Inoue now, so much better to do some cleaning in the lower weight class for now.