If you haven't used it in two stints, you don't need it
The 'just in case' kit is what kills you. Wait until you've actually needed something before you pack it for next time. Most contractors find that after 3-4 contracts their kit shrinks by half.
Multi-purpose beats specialised
One pair of soft trainers for evening walks AND gym sessions. One rain jacket that doubles as a smart-casual layer. One book on the Kindle, not three paperbacks.
Re-supply locally, don't carry
Toiletries, snacks, basic clothing — buy at the local supermarket on the first evening. Saves luggage weight and supports the local economy slightly. Costs about £15 for a full toiletries restock.