Given that Kurt Sutter has stated he wants SOA to have 7 seasons and the ratings for the show continue to climb, it's hard to believe that Jax would really walk away from the club, despite his own declarations. Likewise, it's hard to believe that the club won't get out of bed with Galindo. So all the movement in the episode--Jax realizing how bad the situation is and wanting to leave with Tara, the reappearance of the Niners as partners with LS, Potter going to Otto--is conditional on how this season actually turns out. We'll have to see if there really is a big payoff at the end of the season which stays faithful to the characters and extricates them from the cartel.
I don't believe Tara will be killed, but if she does, I don't think it'll be too big of a loss. Tara hasn't had much to do since last season, so her impact on the show if she dies will be how others react to her death, not a loss of what she was doing (which was essentially raising kids and reading letters).
On the other hand, I can envision Clay being killed or severely marginalized by the end of the season. Gemma and Uncer pretty much conclude that Clay can't be saved, and all Gemma can do is keep Clay close to try to sway his mind. Then, Clay immediately defies Gemma and calls the hitman. With this, Clay is past the point of no return, if he hadn't been already. If she is so forgone, what kind of character growth will he have? Probably none. And if so, why would remain on the show, if not for being a plot device?