Mark James Boyd wrote:

Well, I've looked into canards, and as a previous
poster pointed out, modern canards sacrafice a bit of
efficiency over trailing tailbooms.

So if this is out, canting engines to the side, or down, seems
a good choice. Doing this with a single engine is awkward.
So perhaps the engine right out the tail?

Hmmm....
Look at Max Barel's "Graal" experimental glider in France.
http://perso.wanadoo.fr/max.barel/Graal/overview.html
Seems to work rather well.