Summary of suggestions:
Players that log out inside a certain or any building spawn back in a forest close by.
players nearby someone logging in can see and/or hear him/her before he/she can see anything.
Items picked up by a player who shortly appears on another server disappears.
If any of these suggestions wouldn't work please tell me why. If they could work but need some alterations to them I would be happy to discuss. I do think this is a problem that should be looked in to.