And you expect users to sit down when they first log in and evaluate all the various options for software, pick one for each task? Nobody wants to do that. They want one application that just works.
This works great for new users. But what about those who have been using the system for some time? Last year your default was application Foo. This year it's application Bar, with application Foo suddenly no longer in any menus. Do you expect the users to blindly acquiesce and switch to your new default choice in the middle of trying to do actual work?
Not every user will be sitting in front of your desktop for the first time. Some of them will be upgrading.
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