It would be great to be able to allocate time against a bill of a different client, for example, when time has been posted to an individual partner but the partnership is the one that's billed. At the moment, you have to individually move each time record to the partnership before it can be allocated correctly. Likewise, when time is posted to a director, but the company is the entity that's billed
I see that this idea has already been suggested under "cross billing". So go and find and upvote that.