Young did not have a playmaker or a striker who could make him more effective at Aston Villa.
If United bring in a Snjeider or similar playmaker, then there is less playmaking responsibility on his shoulders, and the ability to play more on the last man's shoulder and exploit his speed. Even without Sneijder, the ageing Giggs/Rooney can still provide that.
Rooney is also a much more complete striker than Bent, and will find ways to play Young in more, and do more 1-2s with him. Young will be better at United because he should have more complementary players around him.
