>>1077408272 arc :
Arc 1 : Human vs gem war because there's way too many gems now.
Have the big boss human using old gems tech
Have him be non redeemable showing steven that not everyone can change. Right now he managed to almost redeemed a fucking genocidal tyrant because she couldn't control her emotions. Let steven fight a guy who on the contrary control and accept his emotions but enjoy the shit he does.
Arc 2: snake people or other aliens VS gem.
In between the two arcs : some background /more slice of life shit.
No ideas about the movie. Maybe a pink diamond 2.0 prototype made by white diamond before that was left alone somewhere.