I can't find the OP on II Peter 3:9, I used to read it as the elect not perishing and coming to repentance, because of the context of beloved, yes the context is to the beloved and in that context it's talking about judgement. With Peter showing that God does not predestine any to hell, because God desires that all men come to the knowledge of the truth, as Paul did in I Timothy 2:4. He is not willing that any should perish, but that all come to repentance.
When you look at the overall context of the Bible, we see the people coming to Him is by His will, not His desire, want or wish as He does for all men. He also views us as already being His. John 10:14-15 "I know my own and my own know me........I lay down my life for the sheep" not the goats that become sheep, no He see us as sheep, so why would He be concerned with us repenting when He knows His own and knows they will repent and already speaks of them as already having repented?
He's not, with the immediate context being about judgement, how does He view the death of the wicked?
Ezekiel 18:23, 33:11 Have I any pleasure in the death of the wicked, declares the Lord God, and not rather that he should turn from his way and live?
Say to them, As I live, declares the Lord God, I have no pleasure in the death of the wicked, but that the wicked turn from his way and live; turn back, turn back from your evil ways, for why will you die, O house of Israel?
God's desire is that all come to the knowledge of the truth, that none should perish, that all should come to repentance. Will they? No. Does that mean that God is not desiring/wishing/wanting that they would repent? No. Does that mean that He is not desiring/wanting/wishing that any of them perish? Yes.
Peter is saying in, "not wishing that any should perish, but that all should reach repentance." What Ezekiel said in fuller detail.