Quality crosses are always the best ones... early or late they need to be where the striker wants it and and a quality striker will know where he needs to be.
You can put the ball in early every time, but if its not where the striker is or the defender anticipates the early ball in then you've no chance.
The other day against WBA we were trying the early ball but they were not where the strikers were, the strikers were not moving to the ball or they were getting cut out.
We needed to be more inventive in a very crowded penalty area, perhaps hanging a late cross in at the back post for a late arriving Bash or JOC to meet when McG and Billy had gone in early.
I thought at times Billy and McG were the wrong way around. McG was often hitting the front post, perhaps for a flick that never came, with Billy ready to poach at the far post, when we needed Billy to be meeting the low crosses.