Coming from a dedicated customer:

It is quite in efficient and time consuming to add issues to sprints in progress: You have to open the rapid board, go to plan mode, search up the issue, drag and drop from backlog to sprint. With an operation available through hot key or the operations dialog on the issue navigation page one could easily add task to a sprint. If you want to make it really elegant one could by default add to ongoing sprint with the option of adding it to upcomming sprint

In case the issue can be a part of many Rapid Boards, there could be a way to select from a list.