Clowns do very well with each of the fish you list, assuming they are too large to eat for the two efficient piscavores you list (Jag especially, Oscar somewhat). As far as agression, I have found CLs do very well with aggressive centrals; and can be quite happy when kept in a shoal along with big Texas, Carpinte, Black Belts, Midas and certainly oscars and other medium aggression fish. Mine are always out and come to the surface to eat with the Carpinte, Black Belt, and Synspilus. They are one of the best aggressive cichlid tankmates IMO, as long as they are too big to eat if you have fish eaters, and are in a shoal. The only problem you will have with the 180 is that adding 5 or so clowns will give you a large bio-load with what you have, and will require intense maintenance (water changes) to keep it under control. Only problem other than that is that you might like them and their antics more than the centerpiece cichlids. From a aggression standpoint, the clowns will not be the problem, from a victim or aggressor standpoint. Check out cichlidscene.com for some pics of clowns with big centrals/SAs.