A lot of stuff ended up being scrapped in favor of speeding up the game's development.
While there is still hope that events with more than 2 main characters will become main events, they will likely end up being sub-events.
It´s a shame? Sure (At least we will be getting the 3 endings I guess)
But the game is still more than fine and I assume that many simply want to see Takeda doing other things like Sentai or bringing his doodles to reality.
What I really would like to know is that what will be getting as Fantia updates after the main events are finished, coz Tkd first stated that the endings and sub events won´t be shared (I don´t remember if they will be streamed), maybe he will be sharing more doodles or resume Sentai after the main part of the game is finished but yeah, that´s something that intrigues me.