You will not get ahead if you don't win any matches. Grinding is emphasized a lot... You should of course win many games, but you don't have to grind. Just take it easy and have fun. Collect the unupgraded cards, and build a couple of decks with it. Switch AI levels, play pvp. You will still be using the cards later, and you can even sell them, so there is no huge loss.
There's a lot you can try, but it's still a game... and yes, the upgraded cards cost a lot, and yes you need them to get a stronger deck.
