So you do.

Hmm. I could easily see Sabriel as a later Zelda game, yeah (or other single-person RPG type)

Keys is a bit more complicated; later Lucasarts could do it, I guess, but it's actually more story-oriented. I'd see it more as a series of games than a single game -- given that one of the big things there is that the different novels/games are dramatically more -different- than you might expect.