I bolded what I consider to be red flags from what you wrote, so I’ll address those.
1) the career ambition. This is a big one. You can’t force someone to want more for themselves, so this will be a problem. He seems more laid back about advancing than you are, and he may never change. If he’s not pushing for that CPA title now, when he has time to do so, I find it hard to believe he’ll do it later with a wife and potentially children taking up his time.
2) the family. A couple of questions here: have you met them? Do you like them? Does his relationship with them seem dysfunctional? Do they bring the drama and need help from him a lot? If the answer is yes to any except the first two questions, that’s a major issue waiting to happen. You marry your spouse’s family as well, so you have to be comfy with how they interact - unless he’s willing to change in that regard.
3) different vision. This is where I think you know deep down that this won’t work long term. You do not want to continue getting serious about a relationship with someone who has a different vision for the future. It’s too big of a deal to smooth over.
Based on this, I don’t think you’re overreacting and I’d reassess the relationship. The other points you made aren’t huge deals to me personally, but I think the ones I mentioned are major enough to warrant action.