Vlasic is by no means a complete player but he's shown enough in terms of pace, dribbling, balance, and vision to be one of our starting wingers. His age and potential make him even more of a no-brainer. At the very least, he should be picking up 30 minutes off the bench.
Unsworth has been such a great man manager at the U23 level, working with whatever we need him to (like Niasse, for example). I'm surprised at how poorly he's handled some of the first team squad management decisions since he's been in charge.