I’ve been using blender 2.8 on and off to get accustomed but I’m kind of getting worried with the way collections work. Shift+d in the viewport just copies the content of the collection and creates a mess of objects. Shift+d in the outliner does nothing and using rmb + duplicate just crates a link. Instancing isn’t editable nor does it work with physics. This hasn’t been changed ever since I started using blender 2.8 and it renders collections unusable for me. I always thought collections were supposed to work like folders in every major OS. If the files are duplicated inside a folder the files are duplicated inside that folder and if the folder is duplicated the content with the folder is duplicated. Are collections going to be like that or are they going to stay the way they are now?
Current Collection behavior isn't usable and hasn't changed for a very long time
I use collections a lot, while I don’t have the same needs as you I do think it needs to be developed further, a lot further. Collections is so much better than layers so at least we have a starting point. I guess its a matter of posting enough paper cuts and suggestions on leftclickselect in Blender Today. Thank God 2.8 is still a work in progress.
The newest collections have duplicate collection and duplicate linked this is already pretty awesome. But it’s really slow to work with since nothing is selected and selecting has to be done with rmb in outliner. As a quick and dirty fix the duplicate collections items should be selected so it can be moved entirely and quickly after a collection has been duplicated or linked. On the longrun it would be better if collections would work as one item (container) in 3d and other views. To change its content it needs to be “opened”. This creates a very fast and intutive kitbash workflow. Selecting that collection “container” + shift/alt + d should duplicate/link the collection.