Just finished this. What did I think of it?

I thought it was setting up the rookie sister as an important character but turns out she was merely a plot device, and only for 2/5 books. She was also as green in the end as she was at the beginning, there's no character development for anyone. I guess that's just what you'd expect from a short run.

no

I think so, it might not have been a big loss for GW too since we all know they'd rather produce all these comics, books, and TV show stuff on their own, like it or not.

Sisters operate in a fricky place. Bear in mind that I'm way behind on the lore and it's probably even frickier now than when I was into 40K.

Sisters are closer to Guardsmen than Marines. Sisters don't have the legal distinctions and authority that Marines do. But they're more elite than most Guardsmen, and the sisters fall under the authority of the Ecclesiarchy rather than whatever branch of the Imperium the Guard falls under.

There's also a lot less Sisters around than Guardsmen. Sisters kind of operate like Marines, although there's combat Sisters and non-combat Sisters. Sisters are organised into distinct groups that operate like Marine Chapters, sort of. A Sister's "Chapter" will be combat or non-combat. The combat ones go wherever to fight. I don't think they have the level of autonomy that most Marines do - they can't just decide to show up wherever the frick they like or frick off and do their own thing while worlds burn if it suits them (i.e. Dark Angels fricking off because they heard rumours of a Fallen a system over).

They also fight whoever. The fight Tau, Chaos, Tyrannids, Orks, Eldar, Dark Eldar, Heretics, Renegades, Xenos, those new dwarfs with a fricking gay-ass name and even homosexualier lore, the Imperium, Space Marines, Guardsmen, Sisters of Battle, Chaos. You name it they fight it.