I would like to see a feature that allows selecting a gallery to edit after updating the edit of another one. Currently one has to get out of the edit gallery screen, select the gallery to edit to come back to the same screen. A drop-down selector or a similar device may present the other galleries to the user to choose from. This will save significant amount of work while adding titles or captions to multiple galleries.
Another enhancement will be to allow the user to swap, on demand, the caption and title fields. Some add-ons use the title field information which is very difficult to edit in NGG. A radio button, or a similar device may be used to select which field is treated as the "title" field.
Of course, I can imagine the amount of work this may create for the NGG author; but that willingness to improve the code and functionality has made NGG a must-have plugin for WordPress I believe. Thank you.