Funnily enough, I think Cole is more likely to come good next season - there's no doubt of his ability, but at the moment he looks some way off the pace to me (at least based on what I saw against Port Vale). However a proper pre-season and more game time, and I think there's a player there capable of lifting the whole team even if only for a year or two.
Similarly with Bigi really; again what I see is a player desperately short of game time, and as a result he's getting caught out too often. There is a decent midfielder in there somewhere, we just need him to get some energy and confidence back in his game. As with Cole, I think we'd see the best of him next season. I'd be happy to sign them both, personally, appreciate others may differ!