I actually prefer specials to have some depth to them, so there's some variance to how their kits/weapons are played with and against, like how Splashdown can be activated during a super jump and how it (used to) get a slightly bigger radius if you used it from higher up, or how Kraken used to interact with Swim Speed Up (and now had the potential to be affected with Intensify Action but isn't), or how Zipcaster (aside from being, well, Zipcaster) interacts with Ink Saver (Main) and Drop Roller to let you fire more shots and get a boost after landing. Ink Vac is neat on paper in this way (can swallow specials like missiles/booyah completely as well as bombs to give you a nuke) but just doesn't really work in execution even on the hall maps.
Specials like Crab/Inkjet/Trizooka/Bubbler Blower that give you another weapon to use I think are really cool as well, and help close the gap between weapons in range and firepower periodically during the match.
Spammable specials like Super Chump/Missiles have their place as well, like when I'm feeling lazy or just want to press a button and have things go. It's better to not have them be super frequently globally impactful as S2 Missiles were though.
Stingray began to get hated after it got the shockwave buff iirc? It also had crazy objective control in Rainmaker and especially in Tower Control where it was able to keep the tower clear of enemies for an extended period of time.