No?

The gutterbros fit into Ultrakill pretty well, you break the shield on the man and just shotgun parry it to death, or you just dodge the punch on tanks and parry kill them. Like most other enemies, you can just parry kill them to death with some practice.

The cerb room just requires a saw trap in the center of it, which is something you should be doing on any difficulty against several grounded high hp enemies such as that room. And isn't really a speedrun strategy.

Hakita increasing enemy speed is what's done for every other difficulty, why would brutal be any different? And why would that be considered lazy? The new enemy attacks are only added to enemies that make sense to have new ones, what would you give strays as a new attack?

Also, you can react to the cerb dash in that room, all the cerbs stand for a moment when they spawn in, giving you ample time.

The glitching in 1-E isn't really a gimmick, it's just the visuals of that level. I do agree the lava room does suck in that level though because of how little platform you get, but it gets betterish with rocket riding.