I have searched the forum for answers on this, but could not find anything.

I have been told that there are a series of parts that should be routinely changed when the timing belt is changed, being that said parts will be removed or readily accessible at the time.

What should I replace and/or upgrade at this time?

just the belt...nothing else needs to be done. Not sure who told you that but they were wrong.

it's easier to change the waterpump and all the timing belt pulleys while your down there. You don't have to, but its for peice of mind.