Yah, I too use Windows 10. For me, drag-and-drop is also king. But I'm sure a lot of users naturally use "Ctrl + C" and "Ctrl + P", oh oh and not to forget "Windows Key + V" too (at least for Windows users).
Also have a think about multi-file copy/paste. Some users might want them in the same layer stacked on-top of each other, others would prefer the images tiled, whilst some might want each dragged/pasted image placed onto a new layer per image. Would be great to have these configurable in a Behaviour Questionnaire that pops-up during the multi-image paste action, and be set to a certain behaviour for the session too (and configured by app options)