I’d like to give my two cents on some of the ideas suggested above:
Please do not do this. This is inconsistent with the rest of Blender, and it’s a big enough change that it’s really out-of-scope for this project (since it should affect the viewport selection, too). It isn’t too hard to right-click and choose “Delete Hierarchy”, or “Select Hierarchy” and press H to hide the selection.
I agree that the current behaviour is confusing. However… this isn’t the behaviour of the outliner, which extends the selection. Quite a few of the suggestions in this post are out-of-scope, IMO.
I would like to see the selected objects automatically gathered (grouped) in the newly created Collection as soon as the user clicks on the New Collection icon. In fact, just the same behaviour than layers and groups in Photoshop.
Current behaviour (when the new collection is created, the user has to manually move the objects into the collection):
Proposal (once the new collection is created, Blender would automatically move the previously selected objects into the collection):
EDIT :
Maybe a modifier key (ALT/CTRL/SHIFT + LMB) could be used to select objects prior to click on the New Collection icon.
The Sequencer is missing a bin system to organize imported footage. By very little means I believe that the Outliner could work as such. It has already the ability to show scenes and the footage they contain:
The only thing missing is the ability to drag and drop from the Outliner into the Sequencer(like 3D objects into the 3D View).
To add a bit of icing on the cake, the current Sequence outline view mode could be expanded into showing all scenes and the footage in them(the scenes would work as bins).
A double click on a footage file, could switch to that scene, with the playhead placed at the beginning of where that footage is located in the timeline.
Same thing with double-clicking scenes in the Outliner, that could also be used to switch to them.
sync outliner searched objects with viewport showed objects (like unity)
allow a way to search in the outliner an select only the objects with taht name. Actually if you have childrens of one object all parents are showed and selected.
Would it be possible to enable the selection of hidden items from the outliner ? It would simplify greatly the ability to animate visibility without loosing the selection.
The way I read the description of the patch, it only preserves the “Exclude” (=Checkmark) of nested collections, not the visibility (=eyeball) of the objects inside.
The resetting of visibility of objects is not considered a bug (see https://developer.blender.org/T75894).
I also find it very frustrating, hope this can be adressed.
@natecraddock: Happy to see you continuing the outliner improvements! Some ideas, that I think would bu useful (some left over from last year):
Pressing the Numpad “.” to jump to selected object in the outliner jumps to the first instance. It would be good if it would jump to the first real instance of the object. If “Object children” is enabled right now, and the parent is in another collection than the children, then pressing “.” jumps to a greyed-out version of the object, which is not useful.
Always show scrollbar.
Wide scrollbar.
Show Renderability and Disable in viewports icons by default.
Somehow sync renderability with viewport visibility.
Change the names of the toggles to all positive (selectable, enable in viewport, enable in render…). Or all negative (not selectable, disable in viewport, disable in render…). Right now it’s a mix of the two.
@natecraddock It might have been mentioned already, or it might also be on your TODO list, but just to state it in case: Sorting currently only sorts objects in the Outliner. It would be beneficial if there was an additional possibility to apply the sorting to Collections as well. Currently the only option seem to be either manual drag & drop, or using scripted solutions like https://blender.stackexchange.com/questions/157562/sorting-collections-alphabetically-in-the-outliner
Indeed, thin scrollbars are a problem generally in Blender. Maybe it’s outside the scope of an outliner project. The reason I still wrote it in this thread is that the thin scroll bar has the largest negative effect on usability of the outliner. I mean it’s basically a long list, that scrolling through it should be easy is self-evident.
I think that filters popover should contain more filters per type.
In 2020, we should have new object types (Volume, Hair, Point Cloud).
Grease Pencil objects may be as frequent in a 2D animation scene than meshes in a 3D animation scene. But there is no specific filter that differentiate them from Curves/Paths, armatures, lattices.
I am not requesting a filter per object type.
But if you want to find a curve in outliner while continuing to see the whole scene in 3D view, that does not help to have so many things into Others filter.
I would add those filters
Curves for Curves & Surfaces types
Grease Pencil
Volumes for Volumes & Point Cloud & Hair & Light Probes types
Armatures
As is, Others filter would still correspond to Metaballs, Texts, Lattices, Speakers.
Can we please introduce groups so collections can finally be render layers. We need groups with own data block to move, rotate and scale everything as a parent of included objects. So far i can use empty to “simulate” groups but thats work around we need normal groups.
Great you see to continue this project, the last iteration was already a gamechanger and im looking forward to the results of this round:D
I was discussing some hiraries that would be possible for a project and we came across a scenario where it would be nice to be able to have a object as the parent of a collection. Is there something like this planned?
Just to have it in this thread as well. I think it was mentioned that this is supposed to be part of one of the main reworks, anyways, though. So just to spam it one last time
Thank you very much for the continued improvement of the outliner. This is making a lot of a difference in daily work.
Maybe not splitting them up, but a different (colored) icon, or added link icon to the Collection.
I have to agree it’s a bit of a hit 'n miss sometimes when you have lots of them in your scene.
Which in my opinion already solves a bit of issues with Collections and rendering. Using the Collections for grouping things in the scene,. -and- rendering is not really optimal imho. Things can go wrong easily when scenes and render setups get more complex. Having some separation is already preventing this more.
Perhaps it is a little off target but when the collections were incorporated, it was said that the layers of the Armature would adopt the same system once it was tested.
Thanks for all the suggestions and feedback everyone! With 38 replies already, I think it would be silly to attempt replying to everyone, but I’ll try to make some good comments. I would also love more feedback on the main proposed goals I listed. I can clarify if needed, and I’ll add links to the development tasks to my original post after I post this.
@eobet and @jc4d you both mention highlights and active vs selected elements. The Mode toggle and activation column in my proposal plans to address this at least somewhat. I’m also currently fixing selection to make mode toggle, selection, and activation more distinct operations. Some good mockups of the current design are here: https://developer.blender.org/T68498. Also, shift+click on the triangles will expand/collapse all.
@AndrewPalmer I believe selection is working as intended. Ctrl+click to extend and shift+click to select a range.
We’ve had the “remove active state” debate last year but that is part of Blender and won’t be removed.
@radi0n I plan to clean up the context menu, but I don’t expect that to include adding more options. The idea for the context menu is to have some very basic general operations, alongside more hierarchical options.
@nokipaike That is a heavy scene. I tested and I think that the delay is not just within the outliner. Even a normal select has a slight delay compared to the default scene on my machine. Also, holding down the arrow key to scroll is not preferred when there is a scrollbar and mouse scrolling which don’t have the overhead of selection.
@silex I really think autoscroll with drag and drop could be cool as well. One issue I see is that you can drag and drop into the 3D view as well, and having the list scroll in that case might be annoying. You can currently scroll a mouse wheel while dragging and dropping though.
@Josephbburg You can disable non-object data. Look at the filter popover.
@xan2622 I’ve seen lots of suggestions for adding selected objects to a new collection, and I have already discussed it with my mentors. I am not sure yet if that will be default or an option, but it would be useful indeed.
Scrollbars Design: 
