For a few persistent applications (terminal, calendar, chat client, email, ticket dashboard, wireframing tool, etc) I have them tiled on specific workspaces/monitors and I use a keyboard shortcut to jump to the relevant workspace. (I don't know about Elementary, but workspaces is what Gnome recommends for this kind of thing.)
In cases of transient windows (reference materials, docs I'm reviewing, internal wiki pages, screenshots) I just let them pile up willy-nilly on my desktop. When I need to find a specific window that is no longer visible I either tab through the application switcher or select it from the multitasking view.
It may sound like a "messy" approach to window management, but finding an open window using an app switcher or multitasking view seems neither more nor less efficient than finding that same window minimized in a taskbar/dock.
In cases of transient windows (reference materials, docs I'm reviewing, internal wiki pages, screenshots) I just let them pile up willy-nilly on my desktop. When I need to find a specific window that is no longer visible I either tab through the application switcher or select it from the multitasking view.
It may sound like a "messy" approach to window management, but finding an open window using an app switcher or multitasking view seems neither more nor less efficient than finding that same window minimized in a taskbar/dock.