I'm about 10 levels into my Witch Doctoring experience. Thus far I've unlocked about 4 or 5 skills I can use on demand. Each of these skills requires a certain amount of mana in order to cast.
However, no matter how fast I spam any of these skills, my mana amount seems unaffected. I can throw jars of angry spiders like they were 12 for a $1 on sale this week (with coupon), without even making a noticeable dent in my mana. Even when I cast my more "expensive" summoning or debuff spells, the cooldown is far longer than any mana regeneration time I might incur. The mana globe fills so fast that sometimes I wonder if it drains at all.
Is there any point to having mana? Should I be at all concerned about how much I have left or how fast it is regenerating? Is there some point in the game where my mana pool size or regen rate makes any kind of difference?