Amon is already researching very nasty stuff, like irradiate against Zerg, and blinding cloud or mass storm against Terran. As long as the tier 3 upgrades kick in reasonably late, and we don’t face fully upgraded cracklings at the 6 minute mark, I don’t really see what difference this will make.
I think the changes are a step in the right direction, but after releasing stupidly overpowered commanders like Tychus and Zeratul, there is nothing you can bring in non-mutation Brutal that won’t instantly get wrecked. Do you honestly think that the 10 HP combat shield will be noticeable when they eat a shredder grenade?
If you want to improve the Brutal experience, really toning down the OP commanders (Abathur, Nova, Dehaka, Tychus, Zeratul) would be a much better place to start. They simply have too many tools at their disposal to be challenging in the hands of a good player. I play the commanders at random, and I’m genuinely disappointed when I roll a Tychus or Zeratul, since they’re so brainless to play, whereas a Raynor or Alarak makes me smile, since they actually feel like I’m playing Starcraft.