One way that I always rate a team is by looking at the number of NBA players. As a general rule, I feel a team needs 3 NBA'ers to contend for a championship.
Losing Terry and Wright hurts UNC from this standpoint with Hansbrough, Lawson, and Ellington still eligible from that standpoint.
UNC is a much more "normal" team this season, and if I had to focus on a key point for them it will be perimeter shooting. Hansbrough will certainly be the focus of defenses, and especially with the penetration ability of Lawson teams will back away and allow UNC to shoot. Unfortunately, the Heels lost arguably their two best shooters in Miller and Terry. Ellington is certainly capable, but Green, Lawson, and the rest are suspect.