I broadly agree. Paladins not having a deity choice (not even as an option) is really not enthusing me from the standpoint of someone who's interested in the setting. Paladins should 100% have a deity choice-IMHO it should be mandatory since it should be a requirement in the setting-but I'd take anything I can get at this point. I am baffled why it got cut entirely. To get it out the door? Misconceptions on how paladins work in 5e Realmspace? Honestly I'm probably not going to touch the class again if deities aren't added in-this is a big deal for me.
In regards to the Oathbreaker guy-I think both becoming an Oathbreaker and Redeeming yourself is way too easy. The Fellow himself seems to be a glorified gameplay convenience without the writing supporting him to make him look anything but. The same guy who offers you a way to regain your powers should not be the same one to ask you to fall even further. Both IMO should be something you work for. Falling and redeeming yourself should not just be a paltry fee each and every time you pay-a paladin's oath should not be something you just ignore when inconvenient and just pay off like a parking ticket. Nor should a flaming skeleton guy teleport to paladins who break their oath like there's some sort of radar that detects oaths being broken. There should be some sort of quest or something for both of them, or at the very least you should have to actually seek out the npcs that offer these services. I generally regard the writing of BG III to be rather high, but this is just....I have a very negative opinion of it. Lets leave it at that.