More matches = more conquest points to buy gear charms. That and the arena gear are about the only reason but you can accomplish that with dispatch missions. Your dispatch should alternate between conquest points and ancient coins (for accessory charms) or be purely ancient coins once you've got the arena gear. Then you can sell some of your bad epic/heroic gear drops instead of using it as fodder as that'll become a decent source of gold income.
The only other thing I'll say, is when you are ready, make the one time push to get to Master or Challenger. The difference in monthly skystone rewards in Challenger vs Silver is ~1600 skystones. You have Dizzy so building her for high speed, around 190-200 (which you should be doing for PvE anyway), and targeting tanky teams will get you to Master easily but you will have to do 10+ matches a day to jump leagues. But wait until she is geared up so it's an easy road instead of grinding out wins in a mode you don't like.
