I can´t quite understand the reason why you want to build flat, I think the problems you mention are quite easy to solve,
there is a lot of good advice available in these sites, in other forums, Courtnall book etc.
I´m starting my fourth now, so also a newbe. To begin with I used quite long time to build a proper solera,
which really was a good investment and makes my life easier when joining neck, top, sides and back.
I have followed Courtnall´s advice and left ca. 2 cm flat between the edge (sides) and where the dish begins,
it makes joining sides to the top easier because you have 90° angle all the way round.
And I followed advice from these sites about the neck angle, it has been spot on in all my builds.
Marshall Dixon wrote:
you can tape a piece of sandpaper to the top
I do it that way and tape a A4 paper between the sandpaper and the top to protect the top and vacuum the after every 30 - 40 strokes.
Works for me.
I don´t understand the problem with the bindings?