I can't say I've really taken a liking to the Eli character like a lot of people had. Frankly, he strikes me as some sort of character that tries too hard to get my sympathy. It feels like "Hey I'm just a nerdly nerd like you! Isn't that great?!" is what he's trying to tell me every time he's on screen. I also find his personal dilemma of being freindzoned by a hot girl he just met significantly less compelling than almost all other conflicts that were ever presented in the previous two shows.
And personally I find his attempts at humor to fall flat more often than not, so he mostly just comes off as annoying.
Since Air he's intermittently seemed to have both good and bad scenes, though. I can't say I find him universally irritating because every time he is, he usually follows up with something that's either funny or serious that makes me think, "Hmmm maybe he's not such a bad character after all."
In Time, that was in my opinion, exemplified best. I don't think I've ever found him more annoying than when he was yammering on about his favorite movies, unsolicited. I think I actually began to hope Rush or someone would shut him up somehow. Most of Eli's scenes around that time were so awkward that they seemed obviously intended to be so. It didn't really fill me with confidence for the rest of the episode, but everything after that from the character was very good. The stuff we learned about him and his mom was good, the way we saw a documentation of him and the others facing their the threat of death and the discussion on mortality seemed very moving and real to me.
There's no doubt, especially after this episode, that David Blue is a great actor.
The Eli character is one that has a lot of potential, and I'm looking forward to seeing him grow but I can't say that I find him entertaining just because he has a number of aspects to his character sort of similar to myself.