Just to mention, (in the books) at the scene of the Tully funeral for Hoster Tully, Edmure does in fact miss the boat with the flaming arrow three times, and then the Blackfish has to take over and hits it the first try. I always liked the Blackfish, and I think this scene helps develop both his and Edmure's character.
Bryndon the Blackfish is generally an extremely effective leader and goes on to do other reasonably bad-ass things after he slips off at the Red Wedding. (Note: he went off to "find a tree to piss on" immediately prior to the murderous events of that evening.) I hope, generally, the series doesn't forget about him, like they seem to be at risk of doing for a lot of interesting characters.
On the note of other characters that have disappeared: I agree, Gregor Clegane does need to come back. If only for the one on one fight he'll have in the future which should be truly interesting to see on screen.
