Oops, accidentally read the question wrong and voted the wrong way. I do not care that I have to restart the server when you add something. If you do not restart it, then the data base will not be updated, the clients will not be updated. No one can use your stuff you put in the game.
Also, I would prefer resources be spent on other things than trying to do what as far as I know, no other large MMO has been able to do. Downtime is part of an MMO. Maybe it would be useful in prototyping but for an actual live game it is not very efficient. Most players know that the server has to be reset. Best thing to do is to save everything and do an update/server reset once a week.
So, subtract one I do not like vote. I blame it on the migraine.