To address Trunks, no you are wrong.
MMO requires a LOT more balance than SC2 (1v1) or Counter Strike (very simplistic gameplay). The three maps are astonishing well done in terms of balance and the mechanics are fairly solid apart from some professions having a higher use than others in Legion and BoK.
It will take a long time to put in a 4th map. If a 4th map does come out it will likely not be in the automatic tournaments. (as that would require creating a 4th round or randomizing auto tournaments)
People have only just begun mastering BoK and for many teams (a good 80% of them) have not mastered every map or have ideal comp play per map.
So no we do not need a new map and no it will not be mind-numbing as most maps have multiple ways to address them per comp.
The only map that is extremely one sided atm is bunker comps on BoK
If you don't know anything about the other games don't go spreading nonsense. SC2 and CS maps make a HUGE difference.