One of the real beauties of the ODF file format is that most anyone can talk to the people that created it and submit ideas to them for helping to improve it. I've submit a couple ideas - I don't know if they'll make it in or not, but because of how ODF is managed - which is done by OASIS, I am able to.
How does one submit? Well, this is by no means the official method - for that talk to OASIS - but from what I can tell, I'd suggest the following, which is what I'm doing (or trying at least):
1) E-mail the OASIS OpenDocument TC's Office-User lists your idea. This is a public, unmoderated list for ideas about ODF and implementing it. So it should be a good place to (a) see if your ideas is or is not already incorporated, and how feasible it is.
2) Once it has been vetted out a bit by #1, then submit a comment to the ODF TC. This should get you on the way to getting it into the standard.
This should hopefully put you on the right path to getting the format adjusted to meet some new feature.
So what did I submit?
Well, the first time I sent something in was to for an idea I had around enabling multiple people to work on the document. The Office-User's said that (a) it was already supported by DocBook (also supported by OASIS), and that it could be done using some of the features in ODF.
And then recently I sent another idea in - per document dictionary lists to augment the spell checker. If accepted, it would allow user's to be able to set word lists specific to a document so that they don't come up as mis-spelled regardless of whether you open your own document, or you pass it on to another user, who uses a different computer or even productivity suite.
Comparatively, Microsoft's OOXML format does not have this ability. In fact, the only people that would really be able to modify OOXML is, well...Microsoft. The ECMA organization pretty much guarantees that in their standard approval of it - it was designed to be compatible with Microsoft Office, not with meeting the needs of a Document Format. ISO approval would mean that an ISO committee would be able to modify it, but then it wouldn't be compatible with Microsoft Office any more. So, essentially Microsoft has locked up the OOXML format.
So, whether I am implementing a new office productivity suite (e.g. OpenOffice, KOffice, etc; or even just one of my own), or simply being a user of any supporting office productivity suite, ODF is the way to go - I can have a say in its features.
For more information, see the OASIS OpenDocument TC's website.