We are happy to announce that after hearing your feedback we have implemented some improvements to the Stack container.
The new improvements include:
Ability to use top and/or bottom margins for all items
Equalizing margins for all items at once
Alignment shortcuts
Improved on stage dragging
and many more...
All stacks will automatically get the updated features. You will find the alignment and margins control in the inspector.
Equalizing margins:

Top and bottom margins for all items 😎

We are eager to hear your feedback on the improvements and what you think we should do next with the Stack!