I had a good time. Took part in all 3 region splatfests from start to finish and really felt good about the game, maps, and mechanics as a whole. I also was impressed by the netcode, unlike Splatoon 1 where it seems I always wind up in at least 1-2 matches an hour with players that lag sometimes into 3-4 second ranges (not my internet, wired with a fiber connection), I saw such behavior only once in the whole 12 hours (and in that case it was a DC-fest where only 2 players survived the entire match without disconnecting, making me believe whoever was the "host" player was having major issues). I did have a few lobby connection issues but I chalked that down to the build being a beta and am hopeful this will go away with release or in a patch or two.
I tried out all 4 weapons at least a few times and decided firmly on the Tentatek as my main for the day. I tried charger, but for some reason I had a lot more trouble with it than I do in Splatoon 1. I'm not sure if the pro controller has something to do with it due to the different dimensions compared to the gamepad, but I'm not much of a sniper anyway so I don't consider it a big deal. The roller was okay, I enjoyed the vertical flick and the speedups, but rolling around just isn't my style of play. Dualies were a disappointment, honestly. I wish they had kept the ability to jump, or at the very least mapped the roll button to A instead of the jump button, because it is such a jarring change to go from a regular shooter where you jump and shoot all the time to the dualies where if you try jumping and shooting, you're just going to roll off into one direction by accident. All it did was get me into trouble and frustrate me, and as a shooter/splatling/slosher main, I feel like it's not something I can easily adjust to because I'll still be using the jump button with all of my other weapons. Couple that with the disappointing kit on the dapple dualies, and the hype is just gone for me. I loved the tenta missiles, but I have no other reasons to play it.
The maps were pretty good and balanced to my first impression. I really liked the art academy and humpback pumptrack maps, and I REALLY like the addition of the rails on Moray. The rails on Moray give us shooters another option to try and take out or put pressure on the snipers, forcing them to pay attention in three directions now instead of just two. I think it'll give shooters enough of an edge now that we won't have to suffer through 4-6 sniper teams when Moray shows up anymore.