LEJOG (bike) & JOGLE (on foot)

I am doing a 'There & Back' effort starting May 20th to raise some cash for a very worthy cause in memory of a little boy who died last year. See my page & link to blog http://www.justgiving.com/neilcoverley.
I wondered if anyone would like to offer their advice for a route on foot once I've reached the southern end of the West Highland Way.
I am aiming to cover about 25 miles per day. I don't really want to stray onto the Pennine Way as I did this 18 months ago on a North-South walk!
I have 1:500000 Anquet mapping for whole country so don't really want to fiddle around with any routes that aren't do-able at this scale!
Any help would be gratefully recieved!!

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