For blender 2.8 use GroupPro 2.x series.
For blender 2.7x, use GPro 1.1.6.
GroupPro was made because default blender group instances are powerful, but they are not user friendly to work with. With GroupPro I managed to get rid of all annoying features of group instances:
- you can edit any instances on scene, not just the 'source' one
- you can work in recursive way - group instances, can be made of other subgroups, which can be made of subgroups etc. At any stage subgroup can be edited and saved, with all instances updated in real-time
- easy mirroring of selected groups (fixes group instance mirror bug in blender)
- adjusting origin of group, without destroying positions of other instances placed in scene, or in another groups
- nice UI, that makes group instances easy to work with
This makes working with huge scenes with lots of objects easy and gives all the pros of group instances:
- less memory memory usage
- easy selection of multiple objects with one click
Here is video tutorial/demo how to use GroupPro (now new videos):
And blenderartist thread with QA:
You will get free updates whenever there are new ones.
- refactored code for editing and closing groups (simpler, more speed)
- added 'MaxDepth' parameter for 'MakingUnique' groups- Maximum depth for which unique groups will be created. 0-inifinite depth, default=1 (use F6 panel to change maxDepth)
- bug fixes
- Added support for blender 2.78 (version 1.07 won't work with blender 2.78)
- 'Convert to geometry' now has depth option, for which nested groups will be converted to geometry
- add make meshes unique option in 'make unique'
- fix closing group, when it is child of some object
- updated PIE menu
- fix children positions when changing group origin
- correct handing of child - parent relations when working with Groups. Now child objects will maintain their positions.
- added - open nested group - for opening nested groups under cursor (just LMB click on target group to edit it)
- added - shift click on 'Close Group' button to close all edited groups at once.
Update 1.1.4(for blender 2.79 series):
- fixed eye-picker button (opening group under mouse) in orthogonal 3d view
- added - Shift click on 'Open (all)' groups to open selected group with all its subgroups
- If you dissolve group (split into subgroups), remaining subgroups will be automatically assigned to currently edited group (if there is any)
- If you Create group, new group will be automatically assigned to currently edited group (if there is any)
Update 1.1.6 (for blender 2.79 series):
- updated ctrl-x pie (thanks to pitiwazou)
- fixed - setting group origin (child of group would move, now they stay at place). Also made it work on multiple selected objects at once.
- added - 'Bounding Box Bottom' option - for setting group origin at bottom center of group.
- Ctrl+V - paste hotkey operator will now clean group objects automatically when pasting group into new blend file.
- Shift + D - duplicate hotkey operator will now make new duplicate groups unique automatically. Use Alt+D for instancing groups.
Update 2.0.0 (only for blender 2.8):
- support for blender 2.8 (beta)
Update 2.0.4 (only for blender 2.8):
- fix - when creating group, from object that was in in editet group error.
Update 2.0.6(for Blender 2.8 only)
- assign material menu - added option to assign new material
- fixed bugs related to parenting.
Update 2.0.8 and 2.0.9(for Blender 2.8 only)
- fixed initialize function
- fixed flip bug (blender api change)
- flip - now is aware of previously created copy. It will update its position, instead of creating new instance of flip
- Added ability to group collections. See vid: https://www.youtube.com/watch?v=RcreHIRw3f8
Update 2.0.11 (for Blender 2.8 only fix)
- grouping collection now fully supported (Right click in outliner -> 'Group from collection').
- quaternion option added to preferences (prevents gimbal lock that may sometimes happen with euler object rotations, but less user friendly that euler rotations)
- More options for Flip operator (new coordinate systems - global, local cursor)
- Origin to center of bounding box added
Update 2.0.12 (for Blender 2.8 only fix)
- added local mode options: tree, list
- option for linking modifier objects added
- option for linking children objects added