And they are getting heavy inevitable nerfs sooner rather than later, like they obviously should.
Moreover, what you present as "my logic" very much isn't that. SK/ST scenarios merely generate points rather than removing from your opponents, whereas Ball is a juicy cherry on a top of an already very removal-heavy cake.
One more important thing you miss is that SK/ST removal is mostly hardcapped, whereas poison really isn't. Yeah, you can't poison veiled units, but then again, you can't Rebuke out a shielded/sufficiently tall unit, so it's a tie...except poison still has much higher value ceiling.
Okay, first of all, NG's weakness is severely overstated. My best guess is that it's a bad case of withdrawal syndrome after being insanely broken for a while (still have PTSD from forum discussions where people claimed 10 poisons are counterable).
I'm having a blast with Enslave 5 and Assimilation in prorank. Definitely feels like I'm putting more thinking into playing than my SK/NR opponents, but I win as much as I lose (and my winrate would be even better if I didn't dabble in retarded stuff like Tibor x Alchemists occasionally), so there you go. Competitive stuff. Harder to play, but that makes sense with those value ceilings and tricks not tied to the game of numbers. You get lucky with Cantarella/Vilge, you ruin your opponent completely. The opponent goes a bit too tall? Instaloss to mechanics, not even skill. Things like these just can't be easy and reliable, or they would instantly go into broken territory.
Secondly, and more importantly, even if it was as bad as you claim, it wouldn't be a reason to just leave a toxic card be.
NG needs a buff? okay, sure, plenty of bad cards. But that doesn't mean a broken card should be allowed to continue existing just because it's ostensibly carrying the faction.
Didn't realise I needed your permission for pointing out BS. But sure, I'll keep it in mind.