As to your question about your match up it's pretty much random and unpredictable
Nope, it's based on the star count of the decks, ie lower star decks fact off vs lower star decks (and perhaps lower level players too)
That's how people can use 26* decks in T2 with success, since they don't have to worry about a 35*+ matchup, plus they get lv 10s on occasion
You are right, lower star count faces of against lower star count, but not lower level. Most of the expert level 60+ players use 2/3 star Montana or Uppers so they get paired with weak players and win easily with 2 stars, giving them more points.