i have barbs and angels together and they are fine. how some people mess up with this combo is lack of info. i have tiger barbs and veil angels and you just have to follow some rules that apply to alot of the meaner fish lol. barbs (exspeacily tiger barbs) are fin nipers the bigger the fin the more they will nip. if you keep big schools of barbs i.e. 6 or more i have 12 the agresstion is kept in the school for the most part all though this might be a little null invoid in your case becouse in my opinon the rosy barb will be fine the thing that i would think about if i was you is witch fish to design the water parameters around the barbs are hardy fish that can thrive in alot of differnt water parameters i have even seen them in brackish tanks doing fine with figure 8 puffers but the angels are a softer water fish that like slightly acitic water (in the range of 6.9 to 6.0) they can and will do fine in netral water (7.0) but there comfort zones are more in the acitic ranges i dont think your other fish will tolerate such a ph drop for to long it would be very stressfull for them i have a soft water tank with mostly discus in it but a few angels (albino and koi angel) they seem more colorful and i guess happier in my opinon in the right parameters than my tropical comunity tank that is at 7.0 that contains angel and barbs