The top 10 attractions I would recommend include (north to south):
Seaside’s automobile turnaround and oceanfront promenade, famous landmarks dating from the 1920s.
Three Capes Scenic Drive southwest of Tillamook (Cape Meares, Cape Lookout and Cape Kiwanda).
Yaquina Head Outstanding Natural Area in Newport (lighthouse, views, bird watching and beautiful tidepool area).
Cape Perpetua Scenic Area (rainforest hiking trails, views of dramatic coastline formations like Spouting Horn, Devil’s Churn, Cook’s Chasm and Thor’s Well).
Oregon Dunes National Recreation Area (Honeyman State Park and Oregon Dunes Overlook near Florence or hike the John Dellenback Trail south of Reedsport).
Cape Arago (three spectacular State Parks southwest of Coos Bay).
Beach Loop Drive in Bandon (beautiful beach with many rock formations at the edge of the shore).
Samuel H. Boardman State Scenic Corridor (lots of viewpoints and beaches south of Gold Beach).
Hope this helps and happy exploring!