We've spent three summers volunteering on the Oregon coast and have traveled up and down many times. It's an amazing place. Some thoughts:
South coast (Florence & South to CA) Less crowded, more rural area with more back roads in the mountains. Lots of beaches with few people. Not many shopping or dining choices south of Coos Bay/North Bend. A long way East over to I-5.
North - More traffic & people due to easier access to I-5 corridor. More shopping/dining choices. Bigger, more crowded parks. Tillamook Cheese Factory!
All of it - beautiful!