By the time we develop interstellar tech,we probably will still be using ballistic weapons and missiles.

Energy weapons,like lasers,plasma etc have such massive energy requirments that we cant(as an average person) comprehend it.

Railguns(or other mass drivers) have problems with the rails seperating after extended use,so once that problem is sorted,I imagine it will sort of work.

I think if we get to space,on an interstellar level,we will be like Eve Online,bit of everything.