...Okay, Black Summoner jumped the shark, both in the power wank and 'oh right it's a harem, complete with a 'not' little-sister' aspects, urgh.
Apparently reddit is saying that it hasn't bolstered sales at all (and pissed manga/LN readers by omitting some stuff, the LN is much more violent and has some darker magic elements that got PG-ified), so that's that, I suppose.
I definitely feel you. Takina actually had an arc in the show, and I'm having a hard time actually putting together whatever arc Chisato was supposed to have. (She is definitely selfish and jeez do I want that explored as a character flaw.) They've set up a good arc for Chisato to have in a sequel. Problem being we need a sequel.
Yeah, I dunno - I imagine that her arc, if anything, was maybe to be reaffirming her resistance against Shinji/Alan's plan for her to be the best killer alive.....but that never changed at all, to the point of her stopping Takina trying to save her life by killing Shinji, and never had any nuance besides her doing whatever she wanted, as long as no one was killed if possible.
But the show never really even....really acknowledges that selfishness (which is only possible due to her one-in-a-billion kinesthetic eyesight ability) - outside of reinforcing how noble/heroic it is (by contrasting at first Takina, and later on Majima, as being in opposition to her) - or puts up any serious roadblocks that she doesn't near-effortlessly overcome, so I don't know that I have high hopes for it showing up as a character flaw in a theoretical S2.
Heck, given the tone of the show, I don't even know if they'd acknowledge it if there WERE a S2, it doesn't seem like something they're necessarily interested in exploring.
Seems more likely they'd have more 'Lillybell' versus-type shenanigans, with some of the other secret military factions vying to foist Lycoris out, given that the seed of doubt has been planted, +/- Majima and more 'anarchy is good, actually' shenanigans.
....Though apparently, the Chisato/Takina ship is decently sized, the author is a yuri fan, there's already a spin-off manga (which is where the zombies apparently are, I was wondering about that, lol) with more subtext, and the LNs/BDs are doing well, though, so we'll see.