Composite, non-editable figures represent a considerable barrier to reuse.
General points
OA is just the beginning
Open licenses allow for reuse
Explain why -NC harms dissemination
Existing barriers:
Composite figures
Non-editable image file types
Multimedia relegated to supplement rather than embedded (issue: how to archive embedded content permanently?)
No preview for multimedia
Zip for supplement or PDF for article
No file name conventions
PMC does not provide MeSH terms
Attribution stacking
Examples
Biogeosciences
Gil, M.; Rodríguez-Sinobas, L.; Sánchez, R.; Juana, L. (2010). "Evolution of the spherical cavity radius generated around a subsurface drip emitter". Biogeosciences. 7 (6): 1983. doi:10.5194/bg-7-1983-2010.{{cite journal}}: CS1 maint: unflagged free DOI (link)