My AH is a "happy drunk" too. Mellow, pleasant and softly spoken.
His main issue, as I see it, is his utter refusal to take responsibility for the running of our home, lives and marriage.
He gets unpleasant if he needs a drink and it isn't available. Full of anxiety and snappy.
Not all drunks are nasty and abusive. I was when I drank. Thankful to say once I stopped six years ago, that behaviour left me very quickly.
I think a lot of it is to do with what is under the drinking. That determines the drunk behaviour.
AH quit for about ten months recently. He was horrible to live with for most of that time. Such a relief when he picked up again.