Both fish worked well with my community. NO AGGRESSION. Since our tank if only 12G we insisted on the smaller of the two fish. The only sensitivity we had was with the Rosy Barb. Theses *VERY* active fish joined with other slow moving fish in a picturesque tank stand out to a point of being disruptive. If your sensitivities are such perhaps you should add Mollies first, see how they work, and THEN add the Barbs only if necessary.
It's never without anxiety when adding more fish…, because you never want to compromise the balance and health of your community. You really want to be sure and ask all the right questions. Hope that knowing our own situation we have been able to help you. Please let us know how it worked out. Cheer!