Alright, I'm gonna be honest here. I hate Splatlings; hate going up against them, hate using them. I'm going to try my best to come up with some appropriate kits but I'm probably not going to have much to say and they may not be very good. Let's go.
Heavy Splatling Deco
Not much to say here other than the Heavy Splatling seems fairly versatile in my opinion and I think Tacticooler would benefit it as it's an anchor weapon. I initially considered Ink Storm but I felt like that would enable it to have waaay too much control over the map.
Custom Hydra Splatling
So this is probably really good or really bad. Ink Mines return here but I also decided to give it Kraken taking inspiration from the S1 Heavy Splatling. Sounds powerful but remember Kraken Royale has big vulnerabilities before and after use, in addition to the Hydra now being fully exposed and out of position, much like S2's Hydra having Splashdown. Another high skill, high reward style weapon for those bold enough to use it.
Ballpoint Splatling Nouveau
For the Ballpoint, I decided to deviate from S2's Beakons and instead give it a more mobile kit as it's one of the more mobile splatlings. The Splash Wall gives protection as you reposition around the map and the Ultra Stamp gives you an opportunity to be more aggressive. Gone are the days of standing there and ripping Ink Storm after Ink Storm, that's the E-liter's job. Get in there, boi, it's hammer time.
Nautilus 79
Here I've given the Nautilus Suction Bombs and Reefslider to urge the user to move around more and better utilize its mobility. I could also see pairing it with Big Bubbler but I think something more aggro like the Reefslider would be more fun.
That's all for Splatlings *phew*, next will be a favorite of mine, Dualies!