Rather than a linear challenge you could do what me and some friends are doing this summer and book into a holiday cottage in one of the National Parks and plan a different circular ride each day. This would mean you would have a good base to return to each night where you could relax over a few restorative malted beverages.
We're doing it in the peaks, with 3 routes planned in over 3 days, each between 60-100 miles. We're just doing road routes but you could mix it up between road and MTB/CX riding if you fancy the variety.
Way of the Roses is a good shout and one that's on my list for sometime in the next few years. I believe it's all do-able on a roadie, though if carrying my own gear I'd probably go CX for comfort and puncture-protection.
There's also the Yorkshire Wolds Cycleway, but this might be a bit tame for your tastes -
http://www.cycleyorkshirewolds.com/route