First, let me support your decision, supernatural big guys are always handy 🙂
Second: I don’t believe fairy wings would fit characters like these, however, in my opinion, angel wings definitely would – Mighty Seraphims definitely deserve a powerful body frame and appropriate wings (plus some kind of firesword, but that’s just me 😉 ).
Third point is just a note: you may want to add some body hair to that Minotaur, as I see him and as it is now, he looks more Beef than Bull, just saying 😉 😛 B)
Oh, and the lizardman looks just fine to me 🙂