I completely agree with going dis/str for a nightstalker. Because your super is more of a counter than an offensive tool, it's okay to hold onto it. Thus, the int cooldown is less beneficial. As a voidwalker on the other hand, there is no reason not to be slinging nova bombs and grenades as fast as possible. Yeah, you might hold onto it for a little bit to find a good group, but I find it's better to go ahead and just make 2 orbs, because your super will be up in no time with inverse shadow/obsidian mind and bad juju so you can make 2 more. It normally works out to where I'm making the same number off orbs inn the same time as if I waited for the perfect group and made 6 at once. That's why I like to stack int.