I'm not worried about season 4, but I think this reaction is a bit unfair. @Steve_MND is reacting to the information as it's been presented to him; he sees gaps that he has every reason to believe may not have been considered. It's not a vote of no-confidence in the admins; it's working with incomplete information.
If these sorts of reactions chafe, the answer's pretty clear: publish draft rules for public comment. It doesn't have to be all the rules. It doesn't have to be polished, or final; I don't even thing you need to act on the feedback, but give players a chance to react and think about it, maybe fiddle with it in their home games, and it'll be a lot less scary.
There's a reason video games have public betas. Right now, we're just stuck with whatever gets published on release day, and so I don't think players reacting with fear that the admins may have missed something should be all that surprising.
It's not even that broad of an issue. It's not a question of whether or not the admins will miss stuff. So far the admins have said they have basically 0 control over the content of the modules. They are not even designed with AL rules in mind...For example...Death House(and so presumably the rest of the campaign) uses milestone XP...go figure. Season 3 only kinda used milestone XP, it just mainly had bad design issues where there was almost no guidance on how strong PCs were supposed to be at any given point. Don't get me wrong, I was very skeptical about season 3, but I have enjoyed everything I've played through other than chapter 1. The other thing is probably half of the magic item rewards in the entire book are supposed to be rolled randomly, which AL prohibits. Our DMs instead just using magic items that appear in other places in the book and handed out the appropriate certs...technically MOVING treasure around is not the same thing as adding it. The table that didn't do this had multiple 5th level characters rolling off on who got to have the Keoghtoms ointment as their first magic item on their 22nd+ log entry. I can relate, since my 7th level wizard from S1 has 40 sessions and 0 magic items still.
Our group just escaped from the Underdark a full 3 levels behind where the book finally mentions in chapter 8 that the PCs should be level 8 by now. Our group went to Neverlight grove and then Blingdenstone, while another table went to Grakelstugh instead...but they are planning on going right to Mantol-Dereth next(poor guys). Another table spent like 5 weeks at 1st level getting TPKed over and over again in chapter 1. Most of them dropped out, and now the new people get sat there. think they just hit level 3 average now.