I usually like these to either be alphabetical or -if applicable- in logical groups. For this one, I suggest we go for logical groups:
Delete content
Publish contnet
Unpublish content
Make content sticky
Make content unsticky
Promote content to front page
Remove content from front page
"Delete content" does not have a "Undelete content", so it's the only "single" option in the list. As for the rest of the pairs, I chose to have the longest ones as you move down the list and to also place the "do something" ones before the "undo something" ones, but we can reverse the order if that's more preferable.
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A simple way — use Field Group to create a container for fields https://backdropcms.org/project/field_group and CSS Flex оr Grid to alignment.
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