However, that is 49 blocks, and maybe you don't want to make that many. Six rows by six, or 36 squares, with three inch sashes and a three inch sashed border would give you more than enough for your queen size comforter, 93 X 93.
5.) Whether or not the character(s) are good to play as is irrelevant. I have come to the assumption that the strongest characters are Super Sayain 4 Goku, Vegeta, and Gogeta, Omega, Nuova, and Eis Shenron, Super Saiyan God Goku, Whis, Beerus, and Super 17.
Mystic - from what I understand, thanos is a cosmic, so to beat him it's probably best to have powerful mystic champs. plus, 2 of the strongest champs so far are mystic - jug and magik. iron fist is pretty powerful too. so mystic for me gets the nod as best class to have top champs.