My first thought when watching Allen Bailey is that he was badly miscast as an end in the 4-3. While he is very athletic, he was not a good fit for the responsibilities of the position. That spot requires a guy to win one on ones. Bailey really does not have any moves aside from a bull rush to beat a tackle. He is also very raw technically using his hands to disengage from blockers, which means he is not good at getting off blocks.
The Hurricanes moved him inside a lot on passing downs, and he looked much better. There the job is more about using brute force to get through double team traffic and collapsing the middle. Bailey has a quick first step and is very strong and fast. He can overwhelm blockers, using these tools to get to them before they can center their gravity. Very rarely did Bailey not hold the point of attack. It was easier against guards, who are not as athletic as tackles in the college game, but he also showed good strength when lined up against tackles.
His recognition skills are pretty good when he is not engaged. He showed an ability to diagnose plays and rarely overpursued. As far as his motor goes, grading it depends on your definition of motor. He is very good at using his speed to run down backs from the backside. He does have a tendency to stop fighting through blocks, though when he is engaged. He rarely gets moved back, but he again does not do a good job of getting away from them.
When he is engaged, he does not do such a great job recognizing when the ball is coming in his direction to fight through and off blocks to either redirect or tackle the guy with the ball.
Bailey's quick first step isn't always a factor because he is not very good at timing the snap to get a jump.