I'm Paragon 42 and have 55 mana regen. Is that enough ? I run out of mana so damn fast... I'm used to use zombie bears as main but now i'm using bats. I also used to have a ceremonial knife with a +10 mana per seconds but switched to a manajura or whatever it's called and it has no mana regen. At first only 10 mana regen didn't seem much if I lose it but now even tho im doing more damage, i seem to run out of mana ALOT faster.
So how much mana regen should a WD should have ?
Definitely doesn't sound like You have the 4 piece Zunimassa set, otherwise you'd have at least 60 (40 base +20 set). The second helpful perk of the set is the 10 mana per kill. As you're clearing out mobs you're getting little bits of mana back, and they do help in the long run.
I only got 65... I don't usually run out of mana using bats though unless I screw up and cast it more than needed... I use honored guest on spirit walk, so usually I just use that run into a group and as long as I can burn for a few seconds stuff dies, and I get mana from that from zuni 4, and grave injustice... anything else is from orbs and I got like 11 radius... try using a different skill to kill lower amounts of guys... I still rock bears, so I use that from time to time... or you could just stand still burning and let guys come to you