The problem with those unevolved cards is that they evolve after a few games (the low star cards usually upgrade after a few won games) and you have to either buy new ones or change the deck.
Look at the prices of Nanook, Caciope and other low star high power cards at the market.
Since I started playing ELO their price have been steadily going up. No player without a strong cash backup can afford them (i can but i don't want to pay such high prices).
So I like to play with a fully evolved deck. It also saves me the trouble of having to change the deck constantly.
The decks I usually use are ulu - uppers and junta - roots, depending on the decks i play against and the mood i am in.
I also played with montana - nightmare. That really is a fun deck and you can surprise other players with it. Because let's face it, the top ELO players are more or less using the same decks. So sometimes it is refreshing to play against an other deck.