Javier Acuna took a risk in 2016 when he opened Del Pez Mexican Gastropub on the Wilmington Riverfront.  At the time, customers seeking Latin flavors wanted straightforward tacos, enchiladas and fajitas—the cuisine they ordered at Acuna’s Santa Fe Mexican Grill in Newark and Wilmington. But Del Pez is about creative flavors, artful plating and the interplay of ingredients, an approach …