Sizewell is a bit different with the nuclear power stations & fishing boats and Southwold is home to the classic beach hut shot & has a pier & rather cluttered harbour.
Thorpeness is a very picturesque deigner village with fascinating architecture a very large pond & Aldeburgh, with the boats on the beach, is quite interesting too. Dunwich is crumbling away nicely but can be quite moody.
Lowestoft & Gt Yarmouth are a bit grim Further up the Norfolk coast Winterton & Sea Palling are pleasant sandy beaches with dunes, but maybe a touch boring. Happisburgh is rather more interesting (if it's still there...)