Miss Prism, just looked at your pictures of East Anglia. I realized all the wonderful things I forgot to mention. I bookmarked your site to go back and look at some of your other pictures. (I love people's travel photos!)
DeborahAnn, do take a look at these pictures.

From this anglophile's point of view, every corner of the United Kingdom has more than enough to keep you busy for a week. no matter where you settle, you'll love it.

I hope this post has not confused you with an overabundance of possibilities. I am envying your trip.

I like West Sussex and the downs. Highlights (not all strictly in West Sussex): Bodiam Castle, Rye, Brighton, Fishbourne Roman Palace (near Chicester), Portsmouth's Historic Shipyard, especially the HMS Victory, Nelson's ship.

You could attach this area to your Kent/East Sussex itinerary. There are lots of things to see in Southeast England.

We really enjoyed our time in Cornwall, but I'd hesitate to recommend it in October, because so much of what we liked -- the views of the sea, the gardens -- are best in nice weather.

Irishface, yes, all these possibilities do put me in a pleasurable confusion

thanks for all the suggestions, Deborah