Re: OK - Here's the deal.
"1. At least A4 screen - ideally A4 long by Septic paper wide. MUST be reflective ie liquid paper or equivalent)...."
And ... pow, you're already disqualified. The tablet department is over there [hand wave], good luck with the rest of the requirements.
The whole *point* of an e-reader is to replace books that you don't necessarily want in a physical format, and most books are much smaller than A4. Even the technical articles I read can be found in something other than A4 (a process I call "die PDF die"), and now that Kobo handles the EPUB3 format, the number of articles I read on it has increased, although not by a great rate (alas, PDF is not dying fast enough).
I find that my current Kobo is just a little on the large size -- my previous one could fit in most of my jacket pockets -- but I'm willing to concede that for the other advantages.