User Configuration/Clean interface
It would be nice to be able to configure what user groups see in the details pane rather than having to go to each user individually and adjusting their settings.
Rolling this out to people it is very important that they not be burdened with more information than what they need.
It was awesome when you removes products from the menu bar when that feature was not in use and I encourage you to continue on that path. Consider doing the same for Mail, invoice, leads and other things that can keep the UI as clean and simple as possible for optimal user experience.