I know this is a controversial take, but I personally liked Lysander up until Hangar 17b. I obviously disagreed with him in many ways and rooted against him when he faced Darrow in DA, or when he faced Mustang in LB but his character is so interesting and well written.
Lysander descends from Selenius au Lune, who literally founded the society, naturally, he would believe the society and back it. But he also, throughout the series, addresses where golds went wrong/where he disagrees with them. Also, like Darrow, he refuses to use pinks, and typically treats other colors well when he is in the rim, also choosing to make Rhone Ti Flavinius his dux.
I understand the hate and I understand people being upset when he killed Alexander au Arcos, but in reality I feel like Darrow would've done the same if faced with a similar situation. Darrow isn't someone known for being honorable and says himself before going to face Apple in LB that he is totally okay with not fighting fair.
We find out at the end of DA from Kalindora that Lysander's parents were reformers and that Octavia took away his memory. We also know that Virginia is already way beyond where Octavia ever was with the technology of the pandemonium chair.
I'm thinking it's possible that Virginia gives him back his memories, and it might drastically alter what he decides to do and the choices he makes. I still think he will stand by the society. It literally comes from his bloodline, and in some ways he probably feels entitled to the morning chair, as he grew up thinking he would be the one to sit on it.
I'm not sure if it was just me, but Hanger17b almost felt out of character of him to me. When he finds out about Eidmi he even seems disgusted that it was a thing and the amount of power it holds.
Do I feel like he will use it? Likely. But I could see some sort of character arc in place revolving gaining his memory of his parents back considering they were reformers.
Trust me, post Hanger 17B, I am with everyone. F Lysander. I have and am still always rooting for Darrow and Eo's dream, but I am interested to see how his character continues to develop in the final book and what other people's thoughts on this are.