I only use ninja squid E-litre in SZ or TW. Post patch, I feel a lot more vulnerable in close range combat, due to the partial charge nerf. Rather than jumping back to base every time and lose map, after some experimentation, I found that ninja squid really helps slip away to a better location or hide in the tinciest dot of ink, and then snipe them as they turn their back (or ebomb them in their confusion
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). It's an ability that works best when someone is chasing you. I've seen quite a few solo randoms with ninja squid E-litre recently, whether it's new meta or an ability crisis, I don't know.
On swim speed, I don't think vanilla E-litres need it, as you spend most of the game in one spot at a time - you rarely swim. In the same way splatlings don't need swim speed because they're always on foot. Since you use E-litre way more than me, if you decide to trial ninja squid I'd love to hear your verdict, Azure.