Jeff and I (to a lesser extent Metaloid, but I think he gave up on the Voridream awhile ago) never get IT before 6th point. It seems inconsequential, but IT sucking so hard is an integral part of why Voridus is mediocre.
Why is Voridus mediocre? Well, #1, he has big problems handling heroes on tech 1. The fix to that is pretty straightforward- just buff Grenadier damage vs heroes.
Then there's the fact that his late game is quite possibly the worst out of all the leaders. If I lose as Voridus, it's because the game got past the 30 minute mark. Late game Voridus consists of one strategy- Scarab. If the Scarab dies, you lose. To remedy that, IT needs to be buffed. It doesn't need to make infusion last longer. It doesn't even need to increase infusion DPS. It just needs to effect the power of Cataclysm so that Voridus' only nuke doesn't become completely inconsequential past the 30 minute mark. I would recommend putting the majority of the Cata damage buff in IT 2 rather than 1 since Cata at 5th point is extremely potent. It's just that it doesn't scale well vs enemies with maxed out global upgrades.
So yeah. Do these 2 simple things and Voridus will finally shirk the chains of mediocrity.
Buffing grenadiers makes sense. The upgrades need to scale better. Making grens better makes IT more viable.
Cata has a huge potential AOE unlike other leader powers. It should not scale with Infusion Tech. Nukes should not be buffed. The buff to regular infusion should be buffed. Then late game units like wraiths and blisterbacks get better, T3 grens are better, the goo from leader is better.
I am not sure why making cata better is a good idea. I would prefer to not play a game where one nuke wipes my army. Makes other nukes less potent.