-ㄴ다든지 names an example action while implying others of the same kind, and 하다 closes the list: 쓰레기를 줍는다든지 등산로를 정비한다든지 하는 (things like picking up litter or maintaining the trails). With a single item it means doing something along those lines — 조금 더 작은 걸로 바꿔드린다든지 할 수도 있으니까. It sounds considered rather than offhand.