Bear in mind, what I'm about to propose sucked ASS before the on-hit heal was added, but Dusk and Dawn is finally perfectly synergistic with his on-hit build. The following 3 item core, into flex, feels relevant, hard-hitting, and self-sufficient at all stages of the game.
Titanic/Kraken >> DUSK AND DAWN >> Kraken/Bork >> Flex (I've been liking DD/Maw into Jak'Sho.)
PTA for squishier comps, Conq for fatter ones. Generally always Resolve secondary, or Inspiration in a race against the clock against hyperscalers.
This isn't as flashy as crit, and it doesn't snowball as hard, but into thicker teams with heavier frontline and more CC, Viego takes substantially more resources to put down in a teamfight.