This suggestion is kinda silly because it requires new model and new animation and I have neither of those.
Rope would be a new item, like ladders and contruction materials. It would be light (0.5 max), medium length and you could use it to help a teammate in trouble (who is in some pit from where he can't get out by himself).
Also hook and anchor would be even more awesome because people could use rope with hook tied at one end to climb at high places. Combined they should have low weight (1 max).
If this ever get implemented, ladders could be brought back to battle.