help me daydream slash plan!

So I have realized that I save money better when I'm saving for something, something more exciting than 'my own apartment' and more concrete and, frankly, apparently attainable than 'getting out of debt'. Therefore I have decided I am saving for a month two weeks in the British Isles. Ireland, England, Wales. (Not sure if Scotland and Northern Ireland too.) Date to be determined, but this is definitely number three on the priority list, behind 'getting out of debt' and 'my own apartment', so we're talking a few years out at least.

Off the top of my head, places I can think of that I want to visit are Dublin (nowhere specific off the top of my head, but I know there's exciting things in the city), London (ditto), various family-history-pertinent spots in Ireland that I can't actually name without asking my dad the amateur genealogist (but Dublin's among them and I think so is London), Cadair Idris in Wales (Wiki it and look at the first paragraph of the 'myths' section; also, there is a reason this post has a music thingy), Stonehenge, Blarney Stone, Stratford-upon-Avon.

Where else in the British Isles, dear readers, should I put on my list of 'places I absolutely must see while touring the British Isles'? Other than 'some lovely little bed and breakfast somewhere in scenic Ireland where I can sit and write my heart out', of course. :)