So I was reading the toolkit where it was talking about giving condition cards as a reward and it hit me that condition cards might be a good answer for the one bane / one boon rolls that players never have effects for. So I came up with this:

What I do with one <b>boon</b> <bo>:

Gain any beneficial condition for 1 round. (lasts till the end of your next turn)

<b>Or</b>

Gain narrative control, adding detail or
describing the scene. Gain a party fortune point
for good storytelling.

What do I do with one <b>Bane</b> <ba>:

Pick a hindering condition effect for your
character for 1 round (last till the end of your next turn). Gain a party fortune
point for good storytelling surrounding the
choice of condition.

This idea sounds really fun and flavorful, and definitely solves the "let down" of rolling a single boon and not being able to do anything with it.

It will, however, no doubt slow down play quite a bit... at least until the players are really familiar with the many different Condition cards that there are.

A simpler, but admittedly much less flavorful, way to to make use of a single boon or bane might be to allow it to grant a single fortune or misfortune die to the same characters next action. That would be similar to the inspired and demoralized Conditions, but without the delays of the player hunting through a deck.

Don't let them pick if you're worried about gameplay speed. Stack up the beneficial conditions in their own stack, shuffle them up, and flip one to the player when they get a single boon. Then the need to do a quick narrative shift to explain why they would receive it based on the action they performed (which might slow things down, so that part's skippable). They don't want to narrate or want the condition, they discard it...

This worked really well when I used it last night. The picking didn't take long at all, the handing the cards over was the slowest part.