North Norfolk is probably closest to you for a big, empty beach. Suffolk tends to be stony. Dont really know Essex. Clacton has a kite shop - no doubt they could advise. In Norfolk, Brancaster is massive when the tides out and parking is a few meters from the back. Holkom is similar, but with a longer walk. Burnham Overy Staithe is a beautiful beach but about a forty minute walk from the car park. Old Hunstanton is great but I've found the wind a bit less clean there. I favour Brancaster personally. Several good pubs nearby as well, and excellent fish and chips at Eric's.
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