Southport would be better for sailing as it is closer to the Cape Fear inlet which is class A. Wrightsville beach is powerboat heaven and a long way from sailing with a dicey inlet.
The town of southport is very nice and small and quaint and I would suggest Southport Marina since it is right next to town. If that is full...there is another marina South Harbor Village which is newer and well kept but about a mile further from town. They have a deli and I think a pool but nothing else around them. BTW...I would NEVER consider a dock on the ICW...the wakes will kill your boat. Look for something off on a connecting creek. Good luck...nice area.