I really wish I could help ya, but I haven't seen half the shows that you've seen (and am writing them down for future reference) and nearly all of the good shows I can think of you've already seen. Only one I got is that someone recently introduced me to Gokudo, which is supposed to be like Slayers and Rune Soldier. I haven't given it a shot yet, but I figure you'd appreciate something like that more than I would anyways.
I might be able to help you with these three, though, if only just a little:
I'm currently considering "The Familiar of Zero F", "Ragnarok the animation" or "Fairy Tail"....... so any experience with any of those three would be welcome....
The only thing I know about The Familiar of Zero is that it starts out okay and then gets gradually worse as it goes on. I gave up after the first season. I recently read a review of TFoZF, actually, and it sounds like it's no different except it ends surprisingly on a high note, so if you've been watching it for 3 seasons now, it might be worth it to finish it off, if only to see that ending.
I watched 1 episode of Ragnarok, and it was...okay, I guess. I don't remember anything standing out as exceptionally good or bad.
Fairy Tail is probably the best of the 3, but I'm not so sure it's what you're looking for. It's more shounen like Naruto or One Piece. If you don't mind that, go ahead, you'll be in for one heck of a (long) ride.