This series looks... complex. Is this a good starting point? Or should I be looking at a different game?
I don't know if you ever had your question answered, but I'll provide one now. As someone about halfway through it, I can advise that it's safe to just jump in. This isn't as messy as Fate. Everything's presented as if you're new to the nasuverse, and I haven't seen anything yet that requires or benefits from prior knowledge (other than, like, the
existence of one of the main characters in this story in another nasu story, but that connection hasn't played a part at all).
Also, I'm not the biggest visual novel guy - my last one was actually Fate/stay night a few years ago - but the production values in this are far above anything I've ever seen in other VNs. Localization could have used one more editing pass to clean up typos, but I'm satisfied with how the English script reads too.