With pretty much all of these types of games there'll be a cheap deck that's really powerful. You can build that and then spam it to climb the ranks and get more resources to buy another deck. Back when I tried out Master Duel it was the Salad deck. It was pretty fun; I liked it a lot and I had it made on day 1. No idea what it would be currently.
However the games are absolutely designed in a way to entice you to spend money. They will always be slightly frustrating to play without doing that. It's hard for me to recommend any of them if you're not wanting to spend money.