well for preventative maintenance and a clean engine, definitely replace the VC gaskets, you can get them at any parts store in pairs,
as far as the UIM, you don't have one, you have a supercharger sitting in place as the upper intake. and i really don't know if or how often you change the supercharger gasket. but it can't hurt.
LIM...if you're going to do the LIM gaskets, you're going to want to get the aluminum framed gaskets from the dealer, they are much better than the regular old felpro. but if you do that, be sure to flush out that nasty dexcool and replace it with something like Prestone Long Life. If you want to know the effects of dexcool, do a search here and you can see some of the stuff people have seen.
Make sure to flush it or have the cooling system flushed VERY well prior to changing the LIM.
*its 2:30 am, if i made any mistakes, you know why*