I've pretty much hit the ceiling on my barb, with most upgrades costing 1b or so, so I've decided to put funds into gearing my WD. I have about 1.2b right now.
What should I be gearing towards? I tried CoB but I didn't really like it since it felt like I constantly had to chase down mobs to finish them off when they ran away.
Build-wise there are a lot of things, but the big three are Zombie Bears, Cloud of Bats, or 0Dogs. Witch Doctor is pretty well balanced, though, so you can mix a lot of things around (those are the good damage dealers, though, that are easy to spec around.)
0Dog is really expensive to be effective, so I would forget about that spec for now.
In your shoes, I'd get a 5% life steal high dps skorn (your knife isn't that great, so easy to replace.) It makes bears and bats a lot easier to gear around (you can then put some attack speed on other pieces for dps without worrying as much about mana.)
I'd then get a witching hour and crit chance zuni vision for some dps.
I didn't look at your total effective hit points, but I would check into that depending on what monster power you wanted to play at. I personally wouldn't worry about specific stats for all resist, armor or vitality, rather load your character into d3up and look at total ehp (this combines all those together) and try to hit 450k+. Generally for equal ehp, higher resist and armor is a better way to go but you will pretty comparable regardless.
Personal preference, I would get lacuni bracers simply because I really like 24% movement speed (that would probably help your issue with bat range.) Your dps will suffer, though as it doesn't roll high int like your crafts, but it does give you nice attack speed (typically bad for a witch doctor but skorn users can definitely stack 2 or 3 pieces without many issues with mana.) I wouldn't both though unless you can get some crit chance ones.
Edit: one last thing - if after playing CoB a while you still REALLY hate the bat range, try plague bats. They aren't quite as high damage, but they have a bigger range, so its sort of a wash. I think the general consensus is CoB is still better but many folks swear by plague so it's definitely viable.