I think you're probably right but most weapons you can tell what they are simply by their silhouette. For things like the green N-zap like you mentioned, I think it would be more likely that you can put things like stickers on the weapon instead of changing the colors
I like that idea actually. This could work if every weapon's colors stayed the same but you had a given spot or two that you can apply a decal of your choosing. Customization without breaking the opponent's ability to rapidly recognize what's in your hands.
IMO as long as a select handful of weapons get skins, and not for every single weapon and kit, then I think there won't be any issues. Similar to Splatoon 2's hero skins (barring Hero Roller) + Octoshot; most could identify what they were going up against immediately.
In this case you'd run into another problem: player entitlement, heh. If some weapons get skins and customization and others don't, then I guarantee that the people who main the neglected weapons will complain for eternity. Even more than they do already, that is. We already saw that with the have/have not situation that was Main Power Up bestowing the always-controversial Damage Up on some weapons but not others.
If the Splattershot was to get alternate skins, it won't actually be too confusing considering they can just use their designs from the first two games as alternate skins, promo art helps lessen the confusion even further given the Splattershot has been present in more promo renders than any other weapon in the series.
We are already getting alternate customization options within customization options in the upcoming anniversary update anyways, as we will be able to reverse the alignment of some caps and change the size of some shirts.
I think you're underestimating the amount of effort involved in what you're asking. The customization they've offered so far is, to be quite honest, minimal. Take the changing of hat position for example. If you look closely, all the hats they've shown so far are the same model with different textures. Same for most of the shirts, except for the Takoroka Tandem. In those cases they just had do the job of flipping the model and setting up the coding for customization once, then apply that to every model of that type, and call it a day. Splatoon has a LOT of repeat clothing options for the sake of different colors or styles, which is how they're able to pull this off.
Weapons are different. In addition to the previously discussed issues of weapon visibility, every weapon has at most 2 different existing skins outside of stuff like the Splattershot. Coming up with new textures for each unique weapon, even without considering details like stickers, is probably more work than these devs are willing to do. And again, if only certain weapons get this feature, commence the complaining - everyone can wear a hat, but not everyone can reliably fight with the Splattershot.
And kudos if you actually read all of this
