Seeing that these are all state parks you linked....I’m a little hurt.On the far southern coast (Brookings) I like Loeb (closed) https://stateparks.oregon.gov/index.cfm?do=park.profile&parkId=51 and Harris Beach https://stateparks.oregon.gov/index.cfm?do=park.profile&parkId=58
Sunset Bay (near Coos Bay) is one of my favorite coastal spots (camp ground isn't great, but it's a really pretty area) https://stateparks.oregon.gov/index.cfm?do=park.profile&parkId=70
Umpqua (near Florence) is closed https://stateparks.oregon.gov/index.cfm?do=park.profile&parkId=83 but Honeyman is open and it is right on the dunes. https://stateparks.oregon.gov/index.cfm?do=park.profile&parkId=95