Q u o t e: There are a number of traits which are too situational to be deemed worthwhile to invest in. A few examples are:
Increases damage against beasts.
Increases damage against demons.
Increases damage against undead.
We agree, and they were removed from Traits a while back. (not that you could have known that) So yay!
We don't want traits (passives) to be boring. Even the ones that are pretty bland stat increase type passives, we try to make them feel weighty. Trait points are fairly rare, so that lets us make each point feel a lot sexier to spend. Even if they're just standard +% stat passives, they're BIG +% increases. But, there's also a lot of traits that are fairly intricate in what they provide, and to no small degree can be game changers. Either way they'll be a crucial component to any character build.