Info based on Hardcore:
Vitality: get to 50 base in normal upto Diablo, then go 75 until you reach Nightmare Act5, then upto 100 or 125, once in Hell, 150 base.
Passives: I prefer 1 point crit and maxed out Valk, you will be relying on Valk right upto Ancients Hell Diff unless you have good gear.
Bow Skills: Dependent on your preference, mine is Strafe with Freezing Arrow, you will need ML and or MaeK items to sustain Mana Consumption -
....... 1 Base Freezing Arrow and max out Cold Arrow [Think this gives cold damage synergy], you do not need the other synergy for freeze length
....... when using cold damage items like small charms, gloves, belts etc.
If lucky, your first bow could be Witchwild, this can be used to even complete the game, twitchroe armor is also useful, you need to use items that
benefit your zon's survivability rate. Also, you will definately want to find Razortail belt.
End Note: a lot of people hate Strafe, that is because they don't have the patience to use effectively... I prefer it because it does 100% more
damage than Multi Shot and comes in handy vs a single hard monster/boss.
Goodluck... you could also try looking up the hybrid bowazon build.