There should just be marked teleprt doors that can take you from island to island with no fuss or muss.
The whole travel schtick in the shard is why I went there once on Live and never again.
Plus as others have said put something interesting in there in terms of arcs and stories, and maybe shorten the length fo the tfs in there.
Anything other than what is currently there.
They need to FIX the Shard first, before bothering to make it co-op.