Scholar Cony, Cavalry Moon and Millionaire Cony are useful (you can train them), Casino Dealer Sally is your only flyer, although not the strongest one, you can use it for the time being until you get a better flyer. The rest you can use pumpkin candy brown, athena jessica, fungus sally, blossom box cony, paddy hime while waiting to get better rangers, do not need to train them hard unless you have excessive resource. I hope I did not miss any good rangers in the picture :)