I'd recommend getting the food service provider involved in the design process. The architect may be great at their job and be able to make something look good but it might not be efficient. Getting the food service provider involved early on should help to eliminate this.
I'm not privvy to all the details (RFP/Vendors) for when we put a cafe in but did hear the scuttlebutt about a major problem. The designer thought they new everything and ignored input from the food service provider. The result was a cafe that patrons can get in to but they can't get out of...it does look really nice though...
I'd also check with the food service provider to see if they offer any "free" design services. This could help minimize some of your design expense. The provider is the ones that has to live with the design so they have a vested interest.