While I do think you should explore the game yourself a bit more, I'll give you a better time seeing as you were competitive in S1. I mean really the best way to describe what the top tier meta is is to watch Kiver on twitch he streams scrims pretty often with other top players. There are plenty of other people to watch on twitch as well. The best way to keep up with the scene is through watching streams (of tournaments too like BNS on inkTV at 5PM PST. Super good weekly to follow that gets some top tier NA teams to participate) and keeping up through twitter.
This said, the best way to describe the meta as of now is it's very inkjet-heavy. The meta in this game revolves a lot more around specials than the first game. Also, no team will succeed without a solid backline player these days. Most commonly, a splat charger, or firefin (map/mode dependent), a custom hydra, a heavy or heavy deco, explosher, maybe a rapid pro but eehh. Those are the top tier backlines right now. The flex role is becoming less and less prominent but top tier flex weapons are the custom dualie squelchers, h3d if you can get good at it, rapids, and that's about it. Now the meta for frontliners, and you definitely need strong frontliners or you fail, are mostly inkjet weapons or dualies or both. Top tier slayers include tentatek splattershot (vanilla variant is only viable on like moray bc splashdown is so garbage but the kit fits better there), enperry splat dualies, custom blaster, Tetra dualies, some can use range blaster well enough to be a good slayer with it.
If you really want to be good at solo (a worthless goal seeing as matchmaking is pretty bad), the "soloQ meta" if you will, requires you to be able to hard carry, and this is easiest with slaying weapons like ttek, enperries, custom blaster, etc. You can carry on other weapons obviously but the more backline you are the harder it can be to carry yourself to high X powers.
As for abilities, it really depends on your weapon and role, but most would recommend you run 1-2 subs of special saver and quick super jump and a sub of bomb defense (the sub of bomb defense is really most viable for ink armor comps) regardless. Quick respawn is good for frontliners, not close to viable on other weapons. Really just for frontliners, but mostly for high level play, not soloQ. Stealth jump is highly recommended on most weapons even though it's weaker in S2 (as is QR). Swim speed can be very powerful on just about every weapon (though if you're using a splatling, invest heavily in run speed).
That's about it as far as I'm concerned, but I would highly encourage you to watch streams on twitch and pay attention to everything from weapon comps to playstyles to abilities.