I don't think you will find many seascapes at Wistmans Wood Nice place to go though for gnarled trees and rocks etc.
When at St Ives make sure you spare some time to visit the TATE Gallery. There is always something interesting going on there.
Ideally you would need a good few days for the Lizard but one place not to miss is Kynance Cove at low tide.
When in Cornwall food won't be a problem - just eat the pasties
Another thing to remember is once you are in West Cornwall your traveling distances / times between locations will come down dramatically as the land mass narrows and the place is surrounded on three sides by sea.