I've wild camped at Kielder and over in the lakes, but Kielder does have a load of bothies too. I've stayed at The Green and Kielderhead, both of which have been good fun. With the bothies it's a good idea to arrive with a couple of hours of daylight left though, otherwise collecting firewood becomes quite tricky. I am open to new adventures, so if either of you guys have something in mind then I'm happy to go with the crowd.
I'm up in Glasgow this coming weekend, but, depending on family commitments, I may be able to get away the following weekend.