I'm starting to let go of my idealism's on having the majority of the best fighters in the world under 1 banner and seeing all the best fights. The reality is, the UFC doesn't have more than 50-60% of the worlds best fighters under their banner, and they aren't super interested in signing the best fighters and prospects unless they feel they are promotable enough for them.
Having so many elite fighters in Bellator, or looking at how disproportionately dominant Strikeforce and WEC fighters were upon the UFC signing them, it should be pretty clear that a lot of the worlds best fighters and prospects in MMA are not actually in the UFC, that quite a great many are scattered across the world in many different promotions. Hell the UFC has a lot of fighters on their roster that are so low level, they wouldn't hang in ACB, M-1, KSW, Bellator etc. It's a diluted protect that sells you it's brand as if it's the best similar to clothing, when often times you can equal or better quality for cheaper.
Michael McDonald better sign with Bellator next, he's a great Bantamweight ( better than a huge percentage of current UFC bantamweights ), he's still young and has a lot of natural talent, Bellator has a lot of good Bantamweights too.
The other people? Possibly Marlon Moraes, he's voiced interest in leaving WSOF and it looks like he now has. However Moraes is also open that he isn't interested in fighting for the UFC for the sake of it, he needs to be paid what he deserves. What if Bellator offers him the most out of the negotiations war? Bellator has a lot of leverage in Negotiations now since they don't deprive their athletes of sponsors. Gaethje maybe too? Joe Duffy of course! Bellator needs Middleweights terribly bad, maybe they can finally get their paws on Mamed Khalidov before he retires? Even Gegard Mousasi has chosen to fight out his contract, so he's going into free agency after the Weidman fight is the rumor.
My list of hopeful signings for Bellator are
Ben Askren
Joe Duffy
Mamed Khalidov
Marlon Moraes
Justin Gaethje
Gilbert Melendez