Oh, I always listen to Yahtzee even if I don't always agree with him and find some of his choices for games to review to be bizarre.
I think Bioshock is an interesting example of how likable characters can get you a very long way with games. Andrew Ryan and Atlas are capable of carrying the entirety of the game despite the fact it is "just" a shooter while I love all of the characters from the subsequent games.
Bioshock 2 feels very much like a retread and has serious flaws in the fact you don't actually "feel" like a Big Daddy and move like a normal person. Also, there's no reason Mark Meltzer couldn't have been the protagonist (Dad who's daughter was kidnapped and taken to Rapture). Just make him Sofia Lamb's baby daddy who escaped from Rapture before returning and you have a great plot.
Sarah Bolger did a great job as Eleanor and I really wouldn't have minded her being a protagonist in a future Bioshock. Certainly, she was chipper and likable with a kind of bizarre relationship to the main cast. Sofia Lamb may not have really fit in with Rapture but I also felt she was a strong villain and if not as good as Andrew Ryan, she still had a lot going for her.
Booker, Comstock, and Elizabeth I've already said how much I enjoy but I also feel like the three characters are trapped in a plot which undermines them. The game also leaves a nasty taste in my mouth because of Burial at Sea because it's clear Ken Levine doesn't WANT redemption to be an actual theme of his games. When I first played Bioshock: infinite, I thought the ending with Bookie waking up and his baby was meant to show redemption and how the world had worked out.
A kind of secular Christian ending where Bookie dies for Columbia's sins and saves them as well as himself while Elizabeth becomes the kind of messiah she should have been.
Burial At Sea undid all that.
So, weirdly, I think I prefer Delta and Eleanor. In fact, I think it's interesting how the games change without Ken Levine. Choice is actually important in Bioshock 2 and has a serious effect on the ending while Ken Levine made the entire point of B:I that there's no such thing in video games.