Well, I can only say that Black Company series is great. Of course, Book of Murgen IS weird - after all, it's supposed to be written by a man who "was mad almost half the time"! And Book of The Lady contains discrepancies with other ones - of course! Actually, the way Glen Cook makes different characters tell about the same occurencies differently is what marks him as good writer - one among the best in the genre, from my point of view. It is also very similar with real war memoires...
Of Instrumentalities, I've read only the first one, so don't currently know how well it develops further. His old Dark Empire cycle is surely good enough - a pity it wasn't finished.
Gerge Martin, relative to this, is just boring. It's much more interesting to read actual chronicles on which his novellization is based - and this speaks a lot, as chroniclers didn't aim at being amusing...
I would recommend Robin Hobb for "those who like their fantasy dark". Plus Barbara Hambly, of course. Plus some Russian writers, but they probably won't be translated into English soon...