The neo-splash since it got updated in vol.1 is probably the weapon that competes the most with the tentatek, but even so I don't see any less tentateks then I did before vol.1 and the new nzap won't change that either (well initially with hype and all but overall usage it won't.)
The nzap has great run speed naturally, and yes it's getting kraken/a good kit for it, but just because it has kraken doesn't mean it's broken or breaking the meta by any means. They won't have kraken the entire time even if it comes with 'light depletion', they won't always be able to react fast enough to pop it when a tentatek or whatever weapon inkzookas them, or they get sniped, blasted, you surprise them and shoot them.. and if they do pop it a kraken doesn't signify instant death to you or your teammates. And like previously mentioned it takes 1 extra shot to kill, and that can make a difference. Especially when you and the enemy are trying to out-strafe the other but their weapon needs less hits to splat you.
Also weapons with splash wall already have an advantage over the nzap '83, the main weapon will take too long to shoot down the wall, point sensors won't hurt it, and while kraken will take down a wall it will eat up your special to do so and give them plenty of time to get away.
The nzap will be good, great even in the right hands, but nowhere near meta breaking.
~
I'm most excited for the bento charger, walls will give me so many options with it! The cherry-3 will be fun to test though I don't like the feel of the main weapon so it won't see much use from me. The new splatling will be fun to play with too! The roller will be interesting though I doubt I use it enough to figure out how to use it efficiently.