This is a pic from '71 - two up on the Brenner pass, en route to Athens (and as you can see we're definately of the all-the-gear-all-the-time persuasion). The previous year I'd been the pillion (he'd upgraded!) when we went to Morocco.
Thing is I remember that Yamaha as being quite spacious. Neither of us - or Brigid, the pillion in the picture, complained about lack of space. But I have the same bike in my shed at present and it looks tiny. And I'm not that much bigger now than I was then so it's not a case of me expanding to fill the space available. It must be something to do with what you perceive as reasonable - there were times on our last US trip when I felt short of space on the GoldWing. The 250 would probably fit in the GW top box.