I have a jewel as one of the smallest fish in my tank, she is friends with my smaller distichodus. The tank also has a convict, a green terror, a huge distichodus, some giant danios, and a young 2" datnoid and ctenapoma.
Before being in that tank she was in my planted community tank with all sorts of peaceful fish including kribs and even tetras. I never had any aggression issues. Must be I'm just lucky.