1. Customer service that actually answsers the phone (and speaks english clearly).
2. One reasonable (competative) price for its items without the need of coupon codes or sales.
3. Free shipping for orders over a specified amount (i.e $25 or $50 or $100). From the US or where ever the majority of your buyers will be comingfrom (I hate waiting 2-4 weeks or more for an item the comes from China).
4. Carry all major brands instead of just a select few.
5. Keep your website up to date and running quickly. Nobody wants to use site that is slow (RCU take note)