Sorry but this doesn't hold, according to your logic based on those verses, a person who does evil works is possessed by the devil so it must be resisted, which is just not true for 2 reasons.
both of your quotes explicitly say resist the devil (spiritual being) not people and their evil (physical beings).
Recall that Jesus resisted the devil but not evil works of people.
Recall that we should bless those (people) who do evil to us, not resist them.
Don't recall where but somewhere in proverbs or psalms it says that we should not accuse the devil because that means accusing yourself.
Resisting the devil means avoiding temptations, it is about self rather than others.
I see here, that there is some truth but, at the same time, not necessarily completely scriptural.
Just because one resists evil doesn't mean that he is possessed. He could be influenced or even oppressed.
So let's look at scripture:
Acts 13: 9 Then Saul, (who also is called Paul,) filled with the Holy Ghost, set his eyes on him. 10 And said, O full of all subtilty and all mischief, thou child of the devil, thou enemy of all righteousness, wilt thou not cease to pervert the right ways of the Lord?11 And now, behold, the hand of the Lord is upon thee, and thou shalt be blind, not seeing the sun for a season. And immediately there fell on him a mist and a darkness; and he went about seeking some to lead him by the hand.
Certainly this doesn't line up with your position.
John 8:44 Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it.
This doesn't fit your position either as he resisted them.
HOWEVER:
You are right also:
Ephesians 6:12 For we wrestle not against flesh and blood, but against principalities, againstpowers, against the rulers of the darkness of this world, against spiritual wickedness in high places.
But people many time are used or influenced by these spirits.
Jesus also resisted evil works:
John 2:15 And when he had made a scourge of small cords, he drove them all out of the temple, and the sheep, and the oxen; and poured out the changers' money, and overthrew the tables;
But, as you said, sometime we should repay evil with good.