I LOVE sitting in barb WW's and laughing as I block their attacks. I also have other characters that rape casters if they are giving my sorc a hard time (she has shitty resist)
200% fcr sorcs will be hard to get to but if you telel around a lot you are going to anger people and get sorbed. THat's what I do :P. This build relies on the fact that you can get away from any attack, as any physical attack that lands on you will hit like a mack truck.
If you want a mix between the two, I suggest getting around 50% block with stormshield. This way you dont drain TOO many pts on dext. You'll have decent DR, decnt block, and FCR when you need it.
Keep in mind that I don't build my chars to be inhuman unstopable killing machines. I build them to have fun. If SERIOUS pvp is what you are looking for don't tkae what I recommend too strongly.
My suggestion, Ur going to run into a lot of desynching palidans who will kill ur sorc in 1 hit. Go with max block on switch, U can always put on 2 x 20dex ravens too.