So if i'm reading this right, with this one your respawn time is reduced when you die without killing anyone. That seems pretty fair actually. The old quick respawn is coming back though since we've seen it in the splatoon test fire, so we'll need to know how the two compare.
Special Performance Up and Sub-Performance Up is freaking awesome. They're essentially better versions of special duration up and bomb range up in that they can be beneficial to all specials and subs.
I don't think there is an old Quick Respawn coming back. The 2 demos we've had so far were ones compiled in January and March (which was identical bar The Reef having geographical changes, Musselforge Fitness being playable and the Roller and Dualies swapping sub weapons), which was 3 months ago if you go by most recent build. Everything we've seen after that demo (starting with the Salmon Run and Amiibo tease) has only shown the double Squid icon for Quick Respawn, so they've updated the icon and changed the ability on how it works. The fact it has the same name as the original QR with one squid implies this is the tweaked version of the ability and will be the only Quick Respawn we'll see for Splatoon 2.
As for the ability itself, I am in favour of this change. From the vague information we have thus far my guess will be that you'll receive a minimal respawn timer boost when getting splats in between deaths, and the main effect of Quick Respawn cutting more time will only activate under the condition of getting no splats between deaths, with the effect getting greater the more you die without splatting another player. This is a good way to balance Quick Respawn as it'll be useful on the shorter ranged weapons (and weaker) weapons like Aerospray, Sploosh, Jr. etc. where they can go many respawns where they get no splats due to having to pull off risky flanks and ways of approaching the enemy, so they'll receive the buffs and be allowed to actively go for flanks (Sploosh really relies on those to succeed), whereas weapons that find it easy to splat every respawn will lose the benefits that the current Quick Respawn gives out (Luna, Tentatek, Zink Mini, Dynamo etc.) and those will feel the hurt more from it.
This is a good way of stopping the "Zombie" meta where people throw themselves in to stupid situations with weapons that can guarantee 2 splats in a trade nearly every time and come back in 2 seconds to do it again. This change is also going to help teams who lose a lot of map control where they have this equipped as they'll often get splatted as they leave spawn trying to get back to mid, and they can benefit from the increasingly faster respawn until they finally get a wipe and can push back. My only concern is people using this to cheese Tower Control yet again, because if a whole team stacks it they can quite easily have one person go for the splats whilst the other 3 jump to Tower and deliberately space out their deaths without killing someone to get fast respawns to jump back and spam push Tower again. We'll have to see how this one plays out though.
As for the other abilities that have been touched upon so far from SplatoonJP, I really like a lot of these and how they're making the abilities more useful for all weapons. Special Power Up will be interesting to see how it affects some of the weaker power attacks like Ink Storm and Sting Ray as well as others. I do like the idea of increasing your viewfinder on the Tenta Missiles, as that can make multi lock-ons easier for those key times when the pressure is needed. Sub Power Up is a great way of bringing back Bomb Range Up whilst giving buffs to the non-throwable subs like Ink Mines and Beakons. My concern is how this'll impact Splash Walls, as I don't want this to increase their resistance to attacks, because stacking enough will bring them a little too close to pre-nerf Walls in 1.
Ink Resistance is going to be interesting as a stackable too, as this is going to greatly reduce the effects of one main slot being used as it isn't a "use it and get the same strength forever". This could quite easily go from being one of the best abilities in the game to one of the worst, especially if too many slots need to be given to it to get enough of a boost to make it worthwhile. This becoming stackable as well as the possibility that Cold-Blooded will too is going to make builds a lot more interesting as we have far more contenders for perks on weapons, and still have the same 3 main/9 sub allowance, so I think the meta is going to be very interesting in this game.
As a final note, here's the ability list for what will be seen at E3 with the English names:
