I'm going to put this out there because I'm interested to see if people agree or not. Feel free to up/downvote as you see fit.
I am suggesting PTC get rid of Cognos for a better tool for dynamic reporting, or improve the capabilities around Query builder to allow more dynamic reporting (multi-level BOM type scenarios, multiple data sources in one report, etc.) Something better integrated and easier to use. Would really like to see something an advanced end user could use to build reports without having to do anything physically on the server.
A lot of people I've talked to don't use Cognos at all except the out of the box reports. It can't just be us.
Updating Windchill builds is also a painful process.