Chrysalis is an idiot. She could have accepted Starlight’s offer and “redeem” herself. She could move in with Twilight and Starlight until she’s ready to return to the hive. During seasons 7 and 8, she could get closer to her former enemies and learn about the magic of friendship. Little do they know she would have only been pretending to be reformed in order to gain their trust and come up with an ultimate plan (and this would have been hinted at the end of season 8).
 
Chrysalis could have spent two seasons secretly practicing dark magic, necromancy, maybe researching powerful artifacts to use, while also learning about how to use friendship as a weapon against Twilight and Starlight. Then in season 9 she could use her new powers to free Tirek and Cozy Glow from tartarus and revive King Sombra. This would have been better because it wouldn’t have ruined Discord’s character, and I would have rather not seen Grogar return than have him return the way he did (as Discord in disguise), and I remember wanting Grogar to appear in G4.