Oh christ Endless Eight. Seriously, that's the biggest troll shit in existence.
I'm nearly finished with Magical Girl Lyrical Nanoha: Striker S. I grabbed it because the TVtropes description of it caught my eye (While the title was the reason I always turned away), and I've gotta say I'm some what impressed with the series as a whole. It's definitely leans more on the whole "Power of friendship will get us through!" bullshit, but there's a lot in there that's kinda interesting (Though it really only picks up in the third season; The first two are fine, but it's a little more cutesy then I'm a fan of). It's got a decent system behind it's magic (It's not just there), a decent backstory, and the third season at least gets more mature, though it's never too much so.