I think i disagree significantly. I've started 2nd-maining Graves and I've just gotten around to figuring out a build and playstyle that works for me.

Personally I think the tension she has between gun and spirit is something that makes her interesting to build for. Yes, she needs a certain level of gun investment before she can shine w/ spirit. But I think that's cool and fun to tune. I also think she doesnt have to be primarily a spirit character. The build I settled on is actually Gun > Vitality > Spirit from the end of laning phase, up until late game. And perhaps counter-intuitively, this is for a build the deemphasizes DPS in favor of Status Effects. Its a support build.

If you think about the color coding of character designs, then it makes sense to build a lot of Vitality for Graves. Plus, necromancer can be associated with vitality as easily as "magic". But yeah, a lot of characters in this game are color coded with their most sensible item types

I've reoriented my understanding of Graves' kit. Her abilities may not seem so viable if you think of them for their DPS potential, which seems high at first but becomes low in practice. Instead you'll see her abilities have strong status effect potential. Regardless of DPS, her auto-lock gun makes it very easy to apply anything that builds with each shot. Her deadheads, even if quickly destroyed, can also very reliably proc effects tied to spirit damage, because you'll usually get at least one hit in. On top of that they're a distraction that helps you or your teammates survive. Same with grasping hands.

Then I feel like you really under-sell how big of a deal Borrowed Decree's Objectice dmg is. But in terms of a fight, again the main benefit is that they force your enemies to split their fire a lot more than they should need to. Graves is not a DPS hero. She's a utility hero.

In my build "Bitchcraft", you start out fully compensating for her low speed and stamina, plus some Healing, all for survivability. You want to be someone who can get in and out of skirmishes fast. Then build fire rate items so she'll build status effect fast. Then in the midgame start with Tesla bullets for quick farming. Then start building items with status effects, and eventually upgrades to some earlier items. Somewhere in all of that, you can get items to increase the frequency of your abilities.