Making Plans: Suggestions Please!

I've got some general ideas for areas I want to explore -- places I haven't been (Kensington, Clerkenwell, Lambeth, Kensal Green Cemetery) and I want to walk around the City again with a better eye for what I'll be seeing. I haven't decided on a day trip -- maybe Leeds, Hever or Dover Castle, or Rochester for the cathedral and castle, or Rye or Winchester. Any ideas and suggestions are most welcome. Cheers!