I think what Giselaw suggested is the best idea:
1/ flip your bathrooms- make current family bathroom ensuite and make that adjoining room your master.l bedroom. But I would take a bit off and add it to the current ensuite to make it a bigger family bathroom. I'd expand the study room by knocking into the long narrow bedroom chopping it in half. So your study becomes a good sized 3rd bedroom (not a narrow long one) and your current narrow bedroom is reduced to a box room. Divider wall so the landing now extends to new family bathroom at end and the study. Bonus points for not having 2 other bedrooms share a bathroom wall and hearing the toilet flush.
I know it would mean more work, but really, the long thin room just doesn't work. I would also seriously consider installing a downstairs loo in part of the garage.
It doesn't look like you have put in a new kitchen, you've just painted the one that was already there, so again, if I was a prospective purchaser I would feel a little cheated that other than the extension at the side, all you had done was really give the place a lick of paint (lovely that the paint is though).
I also can't work out how the door to the long thin room goes from the landing? Is it not immediately above the stairs?
I can't find the photos on zoopla. Have they been taken down?