I play Splatoon 1 about as often as I play Splatoon 2; the ranked battle system on Splatoon 2 is just way too forgiving, which invalidates any ranking at all, as lower skill players can just grind their way to the top. (Actually ranking down is almost impossible.) I'm with others in that I want to finally reach S+; I can never get past the S 80, double-penalty wall.
I'm happy with the new specials, except two of them; the Stingray and Ink Armor. The Stingray is so obviously the worst while Ink Armor is so obviously the best that it hurts. The specials in the first game are all bullshit powerful, but they're all about even, unlike Splatoon 2 where I don't want to use the Splat Charger because it might as well not have a special at all. In fact, I'd say balancing might actually be worse in Splatoon 2 than it is in Splatoon 1, even if the game hasn't been out very long. You can't tell me with a straight face that the Goo Tuber can do anything better than another charger.
The absence of Japanese players is really odd in contrast to the first game where they made up about every player in an S rank lobby. Connectivity seems better though, but this may just be in my head.
Most will probably disagree with me, but I think Splatoon 2 is more different than it is better. I, for one, find the music was much better in the first game, along with many other aesthetic things. (Squid Sisters, especially after Nintendo Treehouse's ****ty Off the Hook localization.) There are also some gameplay things, like the maps, where each one felt different, unlike in Splatoon 2 (save Humpback Pump Track). Chargers and Rollers were just made worse when I don't think they needed to be, and possibly as a result, Shooters and Dualies make of 90% of the weapons used.
I was just expecting a little more after viewing the first teaser trailer for Splatoon 2. I got really excited upon viewing the dodge roll to later find out the ending lag kills much of it's utility, and that it can only be used for the Dualies, which should have been apparent to me but wasn't. I was expecting a little more from the Inkjet as well; I basically thought we were getting a faster paced Splatoon, but I realized I'm probably the only Splatoon player who is into Doom, Quake, Unreal Tournament, etc...
And pants. When we said we wanted pants, we wanted them in the same fashion as shirts, headwear, and shoes, not this 3 option, gender-locked (why?) nonsense.