Okay, now that we're done for the night, I had an idea yesterday.
We know Canned Love is basically BAD END. Any other emotion is probably close enough as well. Canned Happiness would be nearly identical, and Hayate's too much of a nice guy to try to can his PTSD to inflict on other people.
What might be worth trying is to make a potion of an Event, that stirs the desired emotion. For example, instead of canning Love, make a potion of Hug, where, after drinking it, the person feels like they get a nice big hug.
That idea led to the idea of making a potion of Music. We specifically concentrate on one of our songs, or play while making the potion, with the intention that when someone drinks it, the song plays for them in their head. It's probably far enough away from a direct Emotion potion to not be MIND WIPE GAME OVER.
We just have to never make a potion of Smooth Sexy Blanket. That will just end horribly.