Ink Brushes, Rollers and the Shooters would benefit from Ink saving to be honest. It is quite noticeable effect.
I haven't considered Cold Blooded either until rank A- but it really affects your movement/behaviour. In Splatzones and TowerControl you want to flank / surprise in order to regain control. Can't do that if the enemy tracks your movement. And I usually play an aggressive role by charging into the enemy so more of a reason for my role to get it. Let us not forget, the duration of Echolocator is also quite long, which means you're struggling for no reason and giving enemy free points/time. But again, this is based on extreme strategy. Average public random-kun wouldn't be bothered and even in high ranks people don't use Cold blooded as you would expect. I guess it is because it occupies a primary ability which people utilize for other effects.
Regarding Defence up. I wouldn't be bothered too much with it. Take a Gal or Splattershot Pro and fire at the dummies with the shields. While you will see the damage being reduced, the Gal still splats in 2 shots and the Pro in 3. A small example with the Splattershot Pro > I have used 2x primary damage up and 2x sub damage up and outputted 99,8 damage versus normal target with 3 shots. Damage up I so far found only somewhat effective for the blasters when you want to output more damage when missing / shooting near. Another effective use which is theorized is for Chargers. So you don't need to fully charge in order to output the full damage. Otherwise the boost is ignorable.
To be honest, I think Nintendo carefully considered the abilities for Splatoon. It doesn't matter how much you stack, you will never have a supreme advantage over the enemy. There will be a difference of course, but that will only allow you to utilize things more effective or efficient but it still boils down to teamwork + personal skill. Even if you had perfect gear, it won't make a bad a player a better one. As in:
- Damage up isn't going to make the spray guns more deadly. Their damage remains poor.
- Speed up isn't going to make you rush the map, but will give make you reach a point ~0.5s sooner than the enemy (If you paint and play it perfect)
- Defence up isn't going to block everything. You still die to Rollers / Chargers / Blasters.
I had argued with few people on a stream that Speed up for swim/inkling might be ignorable. You can get better and more effective things on yyour gear. They claimed I was plain wrong because movement was everything in this game and they say they can clearly see they are faster. But if I analyse the average high ranked person, they are often rolling out with Ink saving / respawn timer / Special up / reduce (depending on their weapon use).
This is why I also question Tenacity as an ability. I cannot decide yet whether I want to keep it or ditch it. While the effect sounds good, it is only working when your allies are down. The thing is, to win you don't want your allies down. Dead allies mean struggling alone. Struggling means enemy is advancing. Advancing enemy means you're losing. Even when I was only one alive, Tenacity didn't make my special gauge fill up at crazy speed. So you never get supreme advantage of being alone, because that would be too much supporting weak comebacks. But then again, Tenacity does help even if just 1 ally is down. And therefore can be considered a good ability too. Arghhh.
Going to use my current Snails to roll the desired gear as posted previously. I really want to see whether I can get my Bubbler up more often without trying to paint too much and this is why I am torn about Tenacity.