All crystals should be Nexus - More choice
Let me share this feeling while it is still fresh. I have just opened a featured 6* and I got Guillotine. It could be worse: it could be Karnak. The feeling is a disappointment.
First of all, I know how RNG works and most of the time, it sucks! And after six years of playing this game, I still get this bitter taste in my mouth when RNG has some fun of me.
However, if I was a new player, opening a featured 6* expecting Hercules or another new hero, I could easily see myself quitting the game.
Surely the Nexus crystal would not guarantee a top pick, but it would allow the player to choose. It could be Guillotine, Karnak, or X-23. Still, it would be my choice.
With over 200 heroes in the game, Kabam could make this adjustment to the crystal. This is not too complex to implement, probably two to three months to change, test and launch. Not a game-changer, but one of these small improvements that have a positive impact on MCOC.