A lot of people have been saying this doesn't really change anything to rotations or gameplay... so for anyone that hadn't given it a shot, or really dug deeper into optimization, I thought I would share how and why the removal of Noxious Gnash is a massive detriment to the job, why it isn't as simple as removing a traditional dot or even Reaper's Death's Design, and some unintentional side effects of its removal.
As a result of the 11 second awakening burst and shorter NG debuff timers, It was imperative to re-up NG just before beginning your burst using dread fangs, ESPECIALLY if you had the resources to double awakening, and also to save a single dreadwinder combo near burst phases to safely re-apply GN for the following coils near the end of buff phase (leveraging the interaction of coils being able to safely interrupt the dreadwinder combo). Removing the debuff means you no longer have to (intentionally) prep or save resources before your burst phase, like holding wyrmwind thrust when buffs were coming back up on DRG. The serpent offerings gauge manages itself easily and isn't really a guage you pay attention to, and your goal is to make sure you DON'T save too many coils for burst phase, as you were guaranteed to gain two charges every 2 minute burst, and at least 1 every other minute. Noxious Gnash was the only true fail point to pay attention to beyond pressing glowing buttons on a railroaded combo.
Furthermore, the change from using dread fangs to apply NG to needing to swap between the two combos has had the side effect of removing the dancing between combos. If you open with 1-1-1, the combo is now and repeating for eternity: 1-1-1, 2-2-2, 1-1-2, 2-2-1. Unless you mess up, you will not find yourself ever pressing 1-2-1, or 2-1-2, like you had to often when using dread fangs or steel fangs as they were. The free-flowingness of following the combo route has ripped out and replaced with Monk's Dragonkick-Bootshine, or DRG's combo cycles, and it is far less engaging than the process of "Do I need to re-apply dot with dreadwinder on cooldown" -> Alternate the second hit -> Hit the right finisher.
In addition to the NG issues, they also went overboard in increasing the length of the general GCD combo buffs, as with 40 seconds to hit the next finisher your 22 second double-awakening combo alongside refreshing NG using Dreadwinder and Spending your coils under buffs meant that you had to intentionally prep every 2 minute by re-applying your NG and prepping the finisher via dread fangs, so that you could use the finisher right on time! These are all not necessarily hard decisions, but the only true conscious decisions to be made given how absolutely free-flowing Viper is made by design. Viper was made free-flowing specifically to load the weight of engagement upon the interactions of abilities to apply NG at the right time, to interrupt each other safely for potency gains under buffs, and to prep finishers ahead of time.
Unlike some changes, this fundamentally changes the job from it's intended identity...!