I'm a barb keeper, so I don't know a lot about tetras, but I'd suggest you do a tetra-only kind of thing with maybe some corydoras or other bottom dwellers if you like. I have a barb-only display with tiger barbs, panda barbs, black ruby barbs, and the only non-barbs I keep are mystery snails, sterbai corydoras, and a 8-year old featherfin catfish.
Mollies are kind of slow and I used to only keep them with other live bearers or similar fish like guppies and gourami.
Basically if the fish you have are similar you should be ok.
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