A lot honest, but my least favorite thing(s) comes down to a couple things, but I feel like I have more to talk about with how bad the weapon kits and balancing are.
Kits seem to be only extremes in this game, where they're either really awful or pretty good, and the bad kit are some of the series worst. And I know that the meta for this game is currently in a healthy spot, but this game really feels like there's a power gap between what's being used and slightly nicher picks.
At least with Splatoon 2, even if its good share of unhealthy specials, at least there was better synergy with each other (most of the time), so it was easier to play off of other specials, even in a soloQ environment, plus a better spread of different specials on weapons rather than just putting the weaker specials on a majority of the weapons. A majority of weapons also don't have a bomb as thier sub, let alone Line Marker just ruining kits. The bad kits don't only feel worse to play, but some of these kits you have to wait for a really long time for, some still not having a 2nd kit; like imagine waiting over a year for your favorite weapon to get a new kit, only for it to get something unusable... what's worse is some cases of this don't even have a good vanilla kit, so then you just gotta hope that your weapon actually gets a 3rd kit with something.
With Splatoon 3 being a game in a modern era, where the game can get balances patches, there's hope for those weapons that just need that extra boost... just a shame that rarely happens. A lot of the buffs that an under powered weapon gets usually don't help it where it struggles. Yeah, Brella is a very weak weapon, two of the problems being bad Ink Efficiency and the damage nerf it got in S2 because Sorella could farm Bomb Launcher easily (don't ask me how that makes sense), so after waiting a year to get buffs it can now regen it's shield faster, a MPU effect it had in S2 that nobody used. Then you also look at Big Swig, and it got some much needed buffs that really helped it out (just too bad it has two bad kits), and I think there needs to be more buffs try to help weapons in places they struggle.
As for the nerfs, I feel like some of them done just for the sake of nerfing, where either the nerf doesn't address the issue with the weapon, or the nerfs become too extreme. Vanilla Splash was the best weapon to use for the longest time, simply because it could farm Crab quickly. Solution...? Nerf the paint range of course, indirectly hurting Neo Splash as well, despite already having issues with being outclassed with TTek, even though they could increase the Special Cost for Vanilla Splash, requiring it to work more for Crab without having to hurt Neo with it. Then you have Machine and Stamper, two really good weapons that dominated. Of course, with something that's super dominate and overpowering nerfs would make sense, and nerfs they got... and kept keep nerfs, even when they were no longer dominate, to the point where they just feels worse to play. Of course, this could just be me having the mind set of "buffs over nerfs", where rather than nerfing something into the ground, buff what's weaker in order for them to have a better chance and nerf what is necessary.
Sorry for the essay of a post, just have a bit to say about why I don't like how weapons are.