Rage is about the emotional power of the human face, and the pleasure comes from watching a group of very talented actors, with only the backdrop of brilliant colors and a few sound effects, create amusing, crass, self indulgent, conceited, ambitious, tender, frail, frightened and, ultimately, touching characters.
There is something of a disconnect between the venue of the "Fashion World" and the violence that erupts. It's jarring and perhaps that was the intention. While the film may have been more powerful if set in a less rarefied atmosphere, it does, nonetheless, tap into an anxiety about arbitrary violence intruding on the lives of ordinary people on buses and subways, in markets, offices, and places of religious observance around the world plunging, in an instant, one's preciously mundane life into tragic chaos. In the last scene, with a stylistic break from the rest of the film, the director focuses our attention on those small, normally unattended moments of life that give it value.
A film in which the action takes place off-screen will not be to everyone's taste, but I think anyone who likes to watch fine actors doing their job superbly will find the film rewarding.