Hi Disorderlypunk, thanks for your response.
Perhaps I need to do a bit more digging, to find some examples on here.
Welding on lugs sounds an interesting idea. Then a bottom set, to take an existing Sport bike Subframe.
Although the width/spacing of an existing Subframe, isn't likely to be the same as the left/right sides of the Fazer rear frame (to line up straight off).
I'm thinking commit to a specific Sports bike tail, buy that Subframe complete (fleabay), then adapt the Fazer rear frame to suit, so ultimately the 4 Lugs welded on will then enable the new Subframe to bolt straight on (as you say). Will require an amount of trial and error. I don't have any welding skills/facilities, so I'd have to rely on a fabricator to complete. Do you do this sort of work? Any idea on how much its likely to cost?
I wouldn't want to go too Eurofighter, it doesn't suit our UK taste (so much)
More just a seamless looking transition front to back, with a more aggressive/purposeful rear end.