Make Arena brackets based on "Total base hero rating".
I have played all sorts of games, PES, FIFA, Pubg, COD, GTA, GOW. Almost all of them have player brackets based on player progression and team strength. But in MCOC there's no way to ever catch up to the top crowd. BECAUSE WE ARE ALWAYS STRIPPED OF OPPORTUNITY TO GROW. Typical example is the arena system, you'll never get a player from arena now since you started playing the game later.
However if brackets are made based on total basehero rating, then it levels the field and gives everyone a FAIR chance to excel and enjoy the game equally. I love the game , but there's ever growing imbalance and rich gets richer with every event or every update.