Overall, I agree with most of this list, but it feels just a little dated. Changes I would make are as follows:
Tentatek S ->A : Inkzooka was what carried this weapon to S, people are both better at dealing with it, you get it less since the nerf, and the meta is much more mid range centric these days. Suction bombs are underwhelming.
0.52 gal A ->S : Inkwall, fast TTK, moderate accuracy, good efficiency, and killer wail make this one of the most versatile, consistent, and competent loadouts. This is my tournament go to and has yielded me my best results.
Forge Pro S ->B : This one pains me as this was my main, however the current state of the game has hurt it significantly. Its excellent performance as a weapon falls flat(lol) against ink walls, which are (understandably) common right now. It can't compete with Zooka output of other weapons and as good as the point sensor is, it does not make up for the shortcomings of this setup. Really regrettable as the splattershot pro on its own is so good.
Luna C ->B : High RoF, Large radius, decent kit, why is this C tier??
N-Zap grey B -> A : Excellent overall weapon performance with Splat Bombs and Echolocator. I'm more surprised you didn't have this at A tier already as I know many really good players(Symph specifically) who use it. I'd almost always have this on my team than aa tentatek.
Slosher C -> B : This could be my bias showing, but the slosher is a situational, albeit still competitively viable weapon. People discount it because they don't quite get how it plays or what it should be used for. Even if you factor in only tournament play, based on my results with it alone it should be B tier, not to mention how dominant it is on 2 zone maps. Burst bombs make up for any deficiency in the weapon itself.
All in all though, solid analysis.
@flc, the fact that you don't think Krak-on belongs where it is or that burst bombs aren't literally the best sub in the game means you are behind in the meta. The Krak-On isn't god tier like some people think, but it has a strong kit and will still show up in tournaments for a while.