The current format of the de-facto one league is casing several problems, like allowing bots with low-level cards to harvest large chunk of rewards and forces well playing gamers to face opponents with much higher leveled cards further in the season.
Several concerns and solutions expressed 
Over a year ago I have proposed a League Format Improvement modeled on European football leagues.
In a nutshell, the differences to current rules would be:
Based on the current number of active players (accounts) I think the following could be introduced:
Champions League
Diamond League
Gold League
Silver League
Bronze League
Novice League
The above numbers would require further investigation and fine-tuning.
With the above changes, I expect any starter pack only (spellbook) accounts would have a tough time to go over the Bonze league, and with a larger player base would be stuck in Novice, thus they would not be able to farm rewards in-proportionate to deck strength and value.
Players would be able to compete for Silver League Champion title etc, making the game more entertaining.
Developers would have more control over the number of rewards distributed each season
When the player base will get larger, each league can be divided to three sub-leagues, i.e Gold League to Gold I, Gold II, Gold III and the number of players (teams), promotions and relegations in each league adjusted.
