Trying to set limits on the time you can spend at the Pool of Life is an interesting concept. But it would lead to other problems. Let's say for instance, you wish to bathe someone who has just been involved in a bloody battle but your time limit is up for entrance to the pool. This would lead to the body needing to ride the ship instead.
I understand that I can become quite annoying when the people you wish to kill are constantly sitting at the pool, but the pool IS a god-given safe zone. Many people use this area to simply sit and discuss with friends they have found throughout the land. It is a place where you do not have to fear ambush while pondering lifes little situations. I understand that some people abuse The pool and they flee there to escape death. but settig time limits on the pool would not only eliminate the abusers, but would also affect those who do not abuse it. Why change the rules that will affect everyone simply because a few abuse the room?
Johnny is spitting water at Sally... well then, no one gets water so we can stop Johnny... a bit too restrictive if you ask me.