Paul,
There are many hidden gems in East Anglia and I'm glad you found Purdis Heath and Woodbridge to your liking. For my taste, Aldeburgh is first rate, and I remember Rushmere with a good feeling, although I suspect it would be too full of gorse for my poor golf today. I think I missed whatever it is that others in the past have enthused about at Thorpeness. Even though it has been wrecked in wartime, there is still something magical about Felixstowe Ferry - but it may be my fondness for MR James and his ghost stories....