For now, the choices could be made out of the already existing games. Doesn't matter how old they are, there're not enough new ones for now.
There're quite a lot of people learning SCI since the release of SCI Studio 3. There'll come more games out, it's just a matter of time. When SCI Studio VGA is released, there'll be even more games. Then it'll be possible to make such awards, although I'd split the graphic awards up in EGA and VGA then (wouldn't be fair otherwise)
-Kon-Tiki-