I really doubt CK faction wars should be a thing, simply because the years I spent playing the SAMP LSRP I witnessed a lot of DMers creating factions, just to have some kind of reason to kill people. Just imagine joining a faction with a freshly made character and a week later, some DM hungry people iniciate a war and you get CK'ed without even having a possibility to develop your character.
Unless there will be some kind of name changes given out by Faction Management when such war happens. But I doubt that would be possible as well, because it would require extra management members to have access to things like giving out name changes and such. Plus, such wars would probably require being spectated by admins, which I doubt anyone would want to do. That is just my opinion though.
P.S I do agree that it would make the game more hardcore and spicier, but at the end of the day I think the advantages of such gameplay fall short to the disadvantages that it can give.