I think tying up with a rope would be cool too, but as FuriousGreg says, its really not applicable in this game mechanics. Cast sleep on someone or a group, kill off the nonsleepers and tie-up the sleeper. Then cast a charm and do some questioning session. Now it don't really work because you have it as a free action to shove your sleeping party member and getting them back in action again. There's never any time for the tactical playstyle you would use in a TT setting with a DM approval.
I really don't know what all the ropes we found in-game are for now. I would like if my strongest jumper (Lae'zel) could jump up, lower down a rope for the non athletic characters in party. But I think Larian doing a great job as it is with many things and I dont think they can manage all things I want.
