Real contract first
WCF should allow implementing SOAP services with contract first, meaning WSDL & XSD. Xml Serializer needs to be able to understand Xml Schema standard better (e.g. maxOccurs, minOccurs, etc) and allow exposing the initial schema instead of generating schema from code in runtime.
Is this stackoverflow question (http://stackoverflow.com/questions/9538378/how-to-prevent-maxoccurs-unbounded-in-xsd-files) what you ask for fix? Sounds like the ask also includes respecting minOccurs.
Looking forward to hearing from you.
Thank you for the suggestion. WCF team is reviewing this suggestion. However, it's not clear what exactly the ask is for. Can someone provides more concrete information (best with samples)?