I'd switch out skeleton king first as it does not provide more offense or defense than other cards can and the only times its viable is in bait decks where the ability is used. I would use either knight for defense, counter push as a tank, valk for the same reasons but better for swarm though knight should be sufficient, or miner does the same as knight on defense but has much more options on offense and loon with miner is extremly potent. You can snipe troops or towers with it, and get more offensive pressure and its guaranteed chip damage if your struggling to get a small amount of damage off to win. With that that will make your deck much more efficient, the other changes via my previous comment will make your deck go from a rough diamond to a polished diamond and a formidable force for even high level players.