I totally agree with you, I think C.A.R.E.S. classification should normally agree with IUCN (If there should be a C.A.R.E.S. classification at all), as C.A.R.E.S. is not a classifier organization and IUCN has a very clear set of rules to establish the conservation status for an organism. Although I believe IUCN has some mistakes, at least when concerns to Central American fish. We also have of course the case where IUCN does not evaluate an organism that CARES wants to consider and so there must be some rules (There are on cares page) to evaluate it.
I also set an additional field in the database for notes, this is for cares "authorities" to establish the reason why to include a certain species in the C.A.R.E.S. program. You can see this filled up in my two species proposed, for example:http://www.cichlidae.com/gallery/cares.php?id=206
There is also place for references in the listing
Beyond all this I consider why C.A.R.E.S. if there is IUCN, well I believe that C.A.R.E.S. should take a more active and practical role in the conservation of species, and list the people and institutions keeping captive populations of certain species (some people may want to be excluded from this and that is fine) but I believe a link has to be established and the fish made available to prevent genetic bottlenecks in isolated captive populations. At least this could be a starting point of action.
Now, not all cichlid species in danger have to be part of C.A.R.E.S. list, so no need to list them all, unless there is of course the possibility top obtain breeding stock and work with them.
Please understand these are my opinions and have noting to do with C.A.R.E.S. official position or goals, I am just trying to establish the link and make proposals for their consideration to work out a better C.A.R.E.S..