It's rare for me to actually want a remake simply on account of improved special effects. Yes, they've allowed me to see The Lord of the Rings and the Marvel Comics brought to life (never thought I'd see either in my lifetime, to be honest). However, does any of King's works merit a reboot because of this? The only one I can think of is Cycle of the Werewolf. I'd like to see Rick Baker handle the effects for this one, with minimal CGI, with someone like Bryan Fuller being in charge because he would do justice the book's central theme of changing seasons.
But there are some of King's books that need a remake simply because the original films are just horribly dated now, and I mean some only. I'd like to see certain new directors adapting his material to film/mini-series again. Just off the top of my head:
Pet Sematary
Salem's Lot (I know it's been done twice)
The Stand as a high profile cable series
Leave the rest alone and focus on the books nobody has optioned yet, e.g. Duma Key, The Talisman.