If I wanted to do it fairly independently, i.e. only really buying food during the year, then stuff I'd add to your list:
A big knife/machete, and another knife as well as your swiss army one.
Trowel. (toilet pits/ burying organic waste).
2 of those 'light my fire' flint things.
Waterproof bags to go inside your rucksack.
3x 1 litre water bottles + a platypus type thing. (remember, a year is a long time and you may break one of the water bottles).
Make sure you bring sewing kit for clothes + rucksack + tent repair.
A small roll mat type thing to sit on while camping/resting.
Head torch, 2x small hand torch + rechargeable batteries (plus solar stuff) or wind up torches instead.
15 bog rolls, or be prepared to use moss.
A couple of notebooks + 3 pens + 3 pencils - for diary or whatever.
Sleeping bag liner - silk
I like the idea of going to live off in the wild somewhere for a year, but I think in practice it would get a bit tedious - especially as the actual properly wild areas of Scotland are not large enough to take up an entire year of wandering.