I would really like to see multi-dimensional structures in the future, right now its pretty complex to build xml based on the current implementation of structures, and local variables are not an option because when the xml changes you have to change them everywhere in your application (because they are copy-pasted over)
When you have a medium sized xml and have a structure that uses other structures to represent it, the number of structures quickly grows, resulting in over a hundred easily for an app that uses only 10 medium sized xml's.
A way of grouping them (other then prefixing the name) is needed, or a way to make one single structure multileveled (why not? the underlying xml in the outsystems platform itself supports it right?)
With the multileveled structures also comes the need for a good mapper like we see in ESB products like Tibco, MuleStudio etc. (instead of just the assign which takes much time/work to make complex mappings with)
It would make working with XML, and exchanging information with other XML/Soap based applications much easier, and Outsystems as a platform more mature.