Technically, while it may be an OOC story, it doesn't have to be an alternate reality persay. Since the Beyonder(or whatever force is posing as it) has the power to rewrite reality anything that happens over the course of the miniseries can be undone at the end as long as the right character gets their wish granted. I'm guessing it'll be Gravity.
On topic though...Toxin could be a good character given that they tone down the teeth and up the conflict between the symboite and the man...of course I'm sure he'll be folded into obscurity after being used for sales. Which is a shame based on the long history of the symbiotes.
Going slightly off-topic, I always thought the drool-y teeth thing was based off of Venoms(Eddie and the symbiote) desire to pervert Spider-mans image as opposed to natural state. Carnage bonded with Cletus so that makes sense that teeth would be inherent to Carnage but Toxin should have been a little calmer in visual form as it was fresh...to me at least, but I don't know every single aspect of the symbiotes.