6th edition needs to be dramatic and give more scope like it used to in Rogue Trader. The squats must return and reclaim their place as the rulers of the galaxy...
40k just sells models, and thats what GW does well. Awesome plastics, easy to convert. The game is just a delivery system with a wonky sci fi story stapled to it. So until a company truly challenges GW in the model stakes the game wont really be that important to them. Would any self respecting true game company ship a codex like Grey Knights? probably not, but the models are pretty so who cares.