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your fully able to pick and select exactly what software you want in most installers (granted i have never used slack myself and it have been years without helping others install it so). allso, haveing them all installed will let the user try them all and keep the one he wants while uninstalling the rest. mandrake is nice this way, mark a selection at the bottom of the software group "window" and you get taken to a tree structure where you can select exactly the stuff you want to install with dependency management so that if you deselct one pacage you get told what packages depend on it and either choose to have them all deselected or just cancel your choice. all of them have nice descriptive info about them and are sorted (to me atleast) logicaly.