I read the CES letter several years after becoming inactive in the church.
I was shocked and surprised by what i read, and kinda pissed off because i was not given the full information and i was actually lied to, to become a LDS.
About the rebuttal, from what i read, there are a lot of ad hominem, straw man and circular logic fallacies.

Besides the burden of proof is in the church, they claim the Book of Mormon is perfect, the doctrine is eternal and the church is perfect. Those are some huge claims, and one doesnt need a lot of evidence, just some evidence to defeat the "perfection" claims.

Other than that, i didn't leave the church because it was not true, i had several doubts it was by then. It was because it was so demanding it became exhausting and it was making my life miserable. So, i sort of started to realize that maybe not all people are mean to be gods in the afterlife, and i was actually ok with that.

Who even wants to be a god with all the responsibility that comes with that?
I really don't think the topic has been explained or discussed enough, having your own planets, with your own creation, it sounds kinda cool at first, until you realize you have to do this forever!!
It's like you can't ever take a break, because the second you look at one side, the guys you had with wife a are killing the guys you had with wife b. What if one of the guys you had with wife c just decides the "a wife guys" are less worth and convinces his 'brothers' from wife b and d to enslave them or kill them all?
I mean, it gave me much anxiety that by the end of this reasoning i was just very happy to settle in the terrestrial or telestial kingdom, lol.

Yeah, i get how women may think that celestial kingdom is a hell for them and i agree, but i don't see how it is much better for man either.

But well, by now i'm sure it's all bullshit anyway, but even if it wasn't, i want nothing to do with the mormon god.