Quote:My main concern with this build is the low physical damage on the WWS.
Occhi's right - CS and DS don't stack, they just fill in each other's gaps. At lvl-70, you'll have 30% chance with the WWS to not get DS on each hit. Lvl-8 CS would reduce that 30% down to about 15%, effectively giving you 85% DS/CS. To get past that point, it's more effective to simply watch DS climb as you gain levels. :) But since it's capped at 100%, there's not much more to gain anyway.
Here's another option for you: Crushing Blow. With FA, Pierce, and Amp Dmg, this build would be ideal for exploiting CB damage in Hell. Since neither helm nor boots are critical items, you can easily get 50% Crushing Blow from Guilluames and Gore Riders. (They'd also give you 30% extra Deadly Strike, maxing DS at lvl-70 without any need for CS.) Another 10-20% CB could be had from Goblin Toe or crafted gloves. I'd also strongly recommend Razortail to get 100% Pierce, maximizing your overlapping FA splashes.
Technical background is this: CB damage is halved on ranged weapons, but FA cold splashes can trigger CB as well as the arrow itself. Monsters' 50% Physical resist in Hell cuts CB damage in half again, but Amp Dmg eliminates PR, restoring CB damage in full. Net result is multiple CB hits on overlapping FA splashes fired into a horde of targets, producing lots of shattered ice cubes. B) Strafe would also score plenty of CB hits.
CB doesn't leech, however, so it wouldn't help your mana issue with high-level FA. Personally, I'd rather use a good Eye of Etlich to extend low-level FA freeze duration, and avoid the need for huge amounts of leech. But pumped Dex, a Might merc, and a pair of mana leech rings added to the Crescent Moon would probably take you where you want to go. ;)