I know this is an old post I am resurrecting. It looks like only some apps have modules created for them. Therefore, I would like to open this up again and re-ask the question.
If I install an app and then try to install another app I get a folder already exists error. Instead it would be great if the installer was smart enough to merge with an existing install. For example, two applications that require a AMP stack, could share the existing Apache and MySQL servers. This could be extended to sharing other common applications like Ruby, Subversion, Git, etc.
This would be particularly helpful for QA environments so that several apps can be installed, updated, and tested prior to putting in a production environment.
I understand there could be version issues depending on software being loaded, but as long as version numbers are documented and the user is given the choice of over-writing, then the individual installing will have the choice.
An alternative would be to develop some documentation on how to manually perform this type of install.