Which keeper makes the best recommendations?

The answer to this question is, of course an opinion. None-the-less, I'd choose Frypan. Frypan has common sense, intelligence, and he chooses best for Thomas. Frypan believes that Thomas can best serve the good of the group by becoming a member of the Council and training the Gladers.

The cook smiled through his beard and sat up straighter. “Shank’s got more guts than I’ve fried up from every pig and cow in the last year.” He paused, as if expecting a laugh, but none came. “How stupid is this—he saves Alby’s life, kills a couple of Grievers, and we’re sitting here yappin’ about what to do with him. As Chuck would say, this is a pile of klunk.” Thomas wanted to walk over and shake Frypan’s hand—he’d just said exactly what Thomas himself had been thinking about all of this. “So what’re ya recommendin’?” Newt asked. Frypan folded his arms. “Put him on the freaking Council and have him train us on everything he did out there.”