Rules-lawyering drama queen... Be nice plz n_n
Ideally I would have ability modifiers not affecting skill bonus by themselves, I would rather high ability bonuses helped you have higher proficiency levels faster.I'm not saying that you couldn't make the distinction, if you really wanted to. I'm saying that, if you do make the distinction, and you include separate modifiers for each, then they are redundant for the task of distinguishing a character's competence within a given level.
A simpler alternative would be to only use the proficiency bonus, say that it represents some combination of natural talent and learned skill, and only use that one bonus (in addition to the level bonus). It would prevent issues where (for example) the cleric is more perceptive than the ranger, when their Wisdom gap is greater than their proficiency gap. It would also solve the annoying old problem where the only way to truly specialize was to have both the maximum ability modifier and the maximum skill bonus.
Edit: An on topic, this isn't necessarily a judgment of value, what I got from the playtest was that PF2 somehow managed to have the bad parts of 4e without the good stuff. I'm still on the fence on whether to give it some of my time of money. I'll have to wait to see what changes we get from the playtest and how it improves before getting invested.