Does God need to come to you personally and to everyone?
No, but it I make a claim that God did come to me personally with a message, don't you think I should be able to provide proof to you of that if I expect you to accept my claim?
Yes of course a sufficient level of proof is a must.
What would I need to do to provide sufficient proof to you?
There are many evidences proving to me that Islam is the truth, but it doesn't work with you and for some others.
There exist claims of evidences. I know the nature of claims. They are easy to make, but evidence is something anyone should be able to examine, test and see for themselves the truth of.
If I say God spoke with me and felt confident in that truth, I would expect of myself the need to provide evidence you could test and answer any criticisms of that evidence to your satisfaction. Reasonable criticisms. I understand there may be a point where your criticisms become unreasonable, but I think I'd had to justify the claim of them being unreasonable as well.
Yes for the others but for me the quran is a proof of God existence.
That's fine. Everyone has to decide for themselves the level of confidence necessary to accept something as true. For me it's being able to provide evidence of my claim which stands up to any criticism. If I can prove to someone who is skeptical of my claim something is true I'm going to have a lot of confidence in my claim.
Where I can't, then I need to reexamine the evidence to see any valid criticism I might have missed, before assuming God put you into a state of denial.