Couple of Ranger Questions

I'm currently level 19 and thus far I've used my passive skill points to reach the piercing arrow circle (just north of the evasion > armor conversion ability) and I've also picked up the first +frenzy charge passive as well. I'm currently working my way around to pickup more frenzy charges, but I had some questions on skills and passives going forward.

I'm only just starting Act 2 and it doesn't feel like mana is an issue between mana leach & potions, but how much INT should I have going forward? I'm using an extra raise zombie gem I had laying around and the 2 zombies I can summon work out okay as far as cheap tanks go, but it doesn't seem practical to expect them to be worthwhile for many levels if I'm not putting some points into INT in order to be able to raise the level of the spell. If I didn't have the zombie meat in front of me, I assume I'd be running away from everything all the time since evasion seems pretty lackluster so far in terms of reliability. I guess the real question is, how viable are zombies as cheap tanks beyond the first difficulty rating?

What curse has everyone found to be the most useful? I assumed warlords mark would be good even though I'd have to pump some str into the build in order to level it up a bit, but that the dual leech would be nice for later difficulties. I haven't gotten one yet, but the projectile one seemed good too, especially since it was changed to also increase damage. The only one I currently have is the critical weakness and I can use the level 1 version of it, but its kind of hard to tell since things die pretty fast at this point in the game.

Projectile weakness without a question is the most useful curse for a dps ranger (assuming that you're going down the frenzy route). I'm lvl 40 and have just reached ruthless - and it's been an indispensible skill, tempered chains is also good for slowing down those faster mobs and bosses. Mana however is now a serious issue for me - I really need to get a hold of the Mana leech skill gem - not forgetting multi projectiles - and then I'm laughing :D.