I've been thinking about putting together a big loop in my locality. It won't be for everyone, there will be lanes linking sections and I intend to put in a little urban off road/canals. I guess it'll never be an ITT but it may be of interest to those looking for a large multiday ride skirting the Welsh borders, Herefordshire and Cotswolds. I can promise epic views and but not the remoteness of the Highlands.
Ps am vv interested in the UK Divide route...even if it's not yet decided.
Don't forget Alan G's Plymouth-Minehead-Taunton; one of the few established long-distance rides in the SW. Good for an overnighter, or you could just blast through and crack it in 24-36hrs if you had the legs.
Note quite a loop unless you include the train between Plymouth and Taunton!
I have a GPX somewhere if you can't find it online.