Cool thing is, even if you ignore new weapons, you can slap -res runes and get strong multiplier for stormblast or iceburst, if you consider quick respec for bosses.
If you spec max iceburst (which is about 50 pierce iirc), and then add pierce runes, one good item with cold pierce, it will be really easy to hit that 170 pierce breakpoint to cap pierce against all non-samael tier bosses. Should improve boss killing ability drastically, as it makes huge difference.
Remember that fighting let's say astrogha with 0 pierce vs 170 pierce means you deal about 6x more damage to it. And dps loss from removing whatever runes in sockets we use for normal play via loss of all stats is nowhere near the benefit of x6 dps gain from pirece. It is big.