I highly doubt about the dps part. Full Venomblade and two-piece provide a lot of dmg which is hard to get otherwise: rare conversions and +skills. I’ve played a lot of it lately.
It is squishy though and very rare rendition of Venomblade can afford to facetank stuff in endgame like cold and pierce do. So i agree about the need of phys res. I’m just not sure everything needs to go to the set. If you just add another 6% to the set… what’s the point in taking any other acid/poison items for melee?