I like Bellingham and rate the area for cycle touring but the PW in that area is dire. It avoids the local beauty spot and leaves town diagonally across a field of thistles before entering another drab forest. The entertainment improves immediately and dramatically on reaching the wall.
The Cheviots disappointed, being badly over-grazed, so the moorland vegetation is dull. (Like Exmoor. Valleys excluded.) On the Scottish side of the fence, things are completely different - a heather moor.
I have caught myself out several times by trying to go light in winter. The result is ending up in a shop trying to buy padded clothing when I already have perfectly good examples back at home.
Evenings are the real trouble. During the day I stay warm through moving while wearing windproof clothes. Once I'm still I start to freeze.
Light sleeping bags can be made to work in winter by wearing clothes, adding bivvy bags and silk liners but a made-for-the-job bag is more comfortable.
A mini Trangia will work in winter but will only light with a spark if I put some sort of wick into the alcohol. Basically, alcohol isn't happy to vaporise in February and gas has problems once the propane has burned out of the mix. You might do better with a petrol or paraffin stove.
Do you really need a 3 or 4 season tent? Most countries have more trees than Britain. Just get something light and cheapish that you can use if accommodation fails to materialise. It will probably be in your rucksack for much of the time. Ignore this comment if you are planning on spending a lot of time in countries like Mongolia and Bolivia.
Everyone knows about NZ's sand flies but it was the possum problem which sent me into huts most nights. They can be really loud and inquisitive.
Big French supermarkets seem to sell all kinds of fuel except for resealable gas cartridges. I used my Trangia on my latest trip and found the French fuel so much better than the stuff available over here that I brought some back.
One problem with alcohol is that it evaporates readily in hot conditions so you need to measure out just what you need.