Are those dialogs common to most X windows programs, such as open, save as, etc, something that you can tweak? I am trying to reduce my use of the mouse and I find it hard with the default one (I am using the i3 window manager on top of Fedora with Gnome 3). If they can be changed, how?
Each widget toolkit provides its own dialog: Athena, Motif, Gtk, Qt, Wx, ... In addition, individual applications may customize the dialogs provided by the toolkit or make up their own. The window manager doesn't matter, what matters is the library that the programmer of the application used.
Apart from Athena, which is hardly used anymore, you won't find alternate presentations of the widgets.
Gnome provides decent ways to cope without a mouse. In the file name list, if you type the first few letters of name, it will be pushed into the name edit box. Gnome hides the name edit box by default, which is annoying, but you can turn it back on. For Gtk2, I have these settings in
[Filechooser Settings] LocationMode=filename-entry ShowHidden=true ExpandFolders=true ShowSizeColumn=true SortColumn=name SortOrder=ascending
For Gtk3, these settings are now configured through dconf, at the location
dconf list /org/gtk/settings/file-chooser/ dconf write /org/gtk/settings/file-chooser/location-mode 1 # filename-entry