It depends on the size of your tank, the aquascaping and the type of cichlid. Your tiger barbs and I. Shark could co-exist with a several varieties of New World cichlids like Fire mouth or Bolivian rams. maybe even Africans, Yellow tail Acei, red fin borleyi or Yellow labs. Your platy and gouromi might not fare too well. My tanks are mixed bags of New worlds, Africans, tetras,
Rainbow fish, Plecos and Synodontis catfish. Research and learn about your favorite fish, if you think it will work, go for it. Take note, your I.Shark will grow fast and large. Plan ahead about possible re-homing.