My two cents worth!

He is my father too
Michael's emotions caught up with him at the restaurant and nearly botched the kill them both

No doubt he was as evil, ruthless, murderous as his father, the original "villain" but if his wife had been like Carmela, he too could have been growing tomatoes, peppers, drinking wine and died in their garden, playing with their grand son

If he was a "villain" from the beginning, then true it is difficult to "sympathize" with him and he gets no sympathy.

Michael originally never had the intentions to get involved because I reckon, initially, he must have thought what his Family does is wrong That's my family, Kay. It's not me.

While he was forced to switch from civilian to murderer, to save Vito in the hospital, I reckon he was not envisaging any further involvement because at that stage, Sonny was alive.

No doubt Michael's choices, decisions, deeds were good, bad and ugly
However so were the circumstances that he was forced into and once in, kill or be killed.

I personally can't see a way out for him after his Baptism massacre
Once a common Mafia hood -- No one is going to give him a pass because he switches to the straight and narrow