I watched one of his videos last night, and now SLE seems less likely to me than ever.
The reason that LSI makes sense is the manner in which he compliments people. He doesn't sound like he's trying to flatter people, he's just point blank stating what he likes about someone.
It makes SLE seem pretty unlikely, since they aren't generally so... complimentary... and the way he does it is inconsistent with LIE (an LIE would most likely try to offer a practical reason why the trait mentioned is a good thing).
SEE could work, in terms of the quality I'm referencing, but SEE's don't generally offer compliments the way Ezra does. (SEE's are usually more like "that's cool" rather than "I like that", though I'm not sure this explanation is descriptive enough for people to understand the distinction.)
The only reason that I'm doubting LSI atm is because it seems like Ezra is appreciated and understood better by the Gammas here than the Betas. It also seems that he clicks better with the Gammas as well.
I also definitely think he's a Positivist. My top pick atm is LSI, followed by SEE (I don't think a Ti PoLR makes sense though).
Anyways, those are just a few thoughts.