The problem when you talk about Eridan is that you always envision him as Feferi would. Yes, he was draining Feferi, but if Feferi held on until he entered his player planet, I'm sure he'd be less of a jerk than he was in Homestuck. He's frustrated, frustrated that his moirail, Feferi, DUMPED for a lowblood (Sollux). And all that pent-up anger resulted in him decimating everyone in the lab, even the matriorb because he was blinded with anger.
This is true, but consider:
You do not have to bend for a relationship that only causes you discomfort if you could simply walk away from it.
I talk about Eridan the way Feferi would, and the way others would, rather than from his own perspective, because Eridan is showcased as a Toxic and Draining person to be with, and I have friends who have been stuck with awful people that reflect many of Eridan’s traits.
Sure, Feferi could have prevented him from going Murderous if she had stuck to him! But why would she have to stick with someone that drains her like that for HIS sake? It’s not HER fault that he’s prone to be a genocidal asshole. And Homestuck puts a great deal on doing what you want to do without stepping over other people’s will and agency. Sticking with him for her sake is being stuck in an abusive relationship, and I, personally, am glad Feferi simply dropped the ball the moment she was able to, and got together with someone she was actually happy and comfortable with.
As for the submission you sent me about Eridan- Not posting it because it’s basically a copy-paste of another post, it is true that Eridan is an excellent Marksman, he’s got brawn, he’s got wits, but the way he uses them is to abuse a position of power over others. It’s toxic domination and demands that belittle others. And that’s the kind of person I regard as a Villain and always will.