Is it a big problem in the UI, if "plus in a circle" is used for both Open and Create on the same web-application page (circled plus is mostly accompanied with the descriptive text)?
If it is, what would be good alternative for "Create" (aka "Add") action?
Eg., will it be ok to have "bold plus" for Create/Add?
For Open I see no common enough alternative. In the context I have, "Open" is perhaps more like "Expand" (and "Close" as "Collapse"). Google image search (not sure how well it represents common sense) brings three different icons: Plus, Chevron (˄) and Four Arrows.