I feel like he is, in many ways, WEAKER than he used to be.
Pre-rework Malz was basically guaranteed a lane-phase win since if he got E onto you (either by directly targeting you or coaxing the visions to leap onto you after they farmed the minions) you would take a massive chunk of damage from the DoT.
But the new Malzahar has the majority of his power placed into the Voidlings now, and the voidings are pretty easy to shoot down and avoid. Malzahar gained a lot of counterplay to nullify his trades and damage, simply by gunning down his minions. Combined with the number nerfs from the rework. he has a lot less guaranteed damage on his basic abilities now.
A player who runs in panic and tries to kite the voidlings will get fucked over, but sharp ones who shoot down the fist voilding before it can spawn others will face minimal damage from Malzahar, and maxing E instead of W won't do a lot to help that since E is mostly supplemental damage now.
He also lost a lot of zone denial power since he no longer has Null Zone to place down as a "Fuck Off" sign.