My concern is that this analogy makes it sound too much as though evolution has a preset goal that the traits are aiming at (which is an error that's already pretty pervasive).

So I would either explicitly address that problem when you're pulling out this analogy, or tweak it to make it sound less telos-y. (Maybe you're playing hangman in French, or some other language you're not fluent in and you're just trying to make any real word of that length? But the more letters you lock in, the fewer possible answers are available?)