Well, you'll need to choose between the lesser of two evils then. There isn't a better way to speed it up aside from getting a whole new processor in your computer. And even that may not do a how lot depending on how new your current rig is.
You *COULD* cross reference the different tables, but I wouldn't recommend doing on whenever anyone joins. It could be done once and hour, or once every 6 hours, or once a day. This would keep them in synch for the most part without adding a ton of extra processing every time someone joins.
