I wouldn't go that far. Sure there are some more guys that they can and will eventually bring over.
But what more can the UFC really do? Urushitani was a top 125er they brought him over he got steam rolled. Ian McCall was the top 125er, they brought him over, he was beat. Da Silva was brought over as the #1 Fly in the world till Ian beat him and he was beaten by a UFC TUF star.
UFC has the best 4 Flys in the world. Dodson, Might, Joe B, and McCall. They brought over top ranked flys from other organizations and they lost. They are trying to bring the best guys over.
You don't think McCall proved he was legit? IMO he beat Mouse the 1st time around and losing to Mouse in a rematch is nothing to be ashamed of. IMO McCall would beat Mouse if they fought again and I still think he is at the very least the 2nd best Fly in the World right now. I think he would beat Joe and Dodson. I think Mongoose could possibly do the same. I think Forminga is still improving, he use to be a pure ground fighter. I think it's possible he could turn into the #1 Fly again. Ian McCall had a bad fight in his 2nd matchup and alot of that had to do with Mouses game plan. But it's very clear he has what it takes to hang with Mouse.