Seems reasonable. It's like the difference between an author who studied The Heros Journey, Guides to immersive Writing, Character Development etc and some other author who just knows what feels right.
But I have to disagree with you on Toffee. Poor guy just wants his finger back.
Jokes aside, I think he wanted to destroy all magic in the universe, because he is the great Equalizer between Monsters and Mewnians.
His kind probably suffered a great deal under Mewnian rule, which is why he joined the war in the first place. The last Episode implies that he neither cares about ruling the Butterfly Kingdom, nor killing his foes. He didn't kill Queen Moon. He arguably just wanted her to experience the full scale suffering of losing her daughter, but in this case he could've tortured her some more.
I think Toffee is a hero in his on regard. A world without magic would make great sense if you are a monster yourself(who experienced the helplessness of your kind against it). Also we have to remember, that he wanted the wand DESTROYED, not in his own hands. It is reasonable to to deduce, that whoever wields the wand, holds absolute power against everyone else.
All of his actions weren't an act of emotion, but calculated. Although his dying scene tainted the whole personality the writers built up on.
He neither seems to enjoy killing, nor unnecessary suffering.