It would also be nice to be able to reinstall a module without losing the data. True, you can save your database but how do you merge or recover the old data???
That will be something to figure out by the development team.. i believe if the data is backed up before uninstalling, there could be a way to restore it.
However, if you know a module will still be needed, it's advisable to only disable and not uninstall. You will be able to have your contents showing anytime you reactivate it.