I applaud the modding community, but I'm willing to bet the percentage of people who don't feel comfortable modding yet desire better sound heavily outweighs the percentage of people who mod their headphones. Not pushing HiFiMan to optimize their headphones for best out of the box experience is letting them off the hook. If stock pads could be focus pads, grill could be more open, etc. for close to the same price, why not encourage them to do that. It'd give more people great sound with less work. Just my two cents.
As an HE400 owner, I'd much rather they just came with better pads, more open grills, a suspension strap, and proper dampening out of the box. It'd certainly save me time, effort, and probably expense. I'll bet they would've gotten better reviews and even more traction in the marketplace to boot.