Unordered elements in XSD with obligatory and unbounded elements?

Question

I have the following element in my XSD:

Answer 1

Three suggestions. Either:

1. Impose an ordering. Almost always the perceived need to allow any ordering of elements is unnecessary in practice.
2. Use XSD 1.1, where maxOccurs="unbounded" is supported on xsd:all.
3. Use a wrapper around the element you wish to allow to have maxOccurs="unbounded". See additionalList in the XSD below for a working example.

XSD with wrapper element to work around unbounded xsd:all limitation