oh dear, don't tell me i'm going to have to go off the radar to avoid singleplayer spoilers...
i'm glad about weapons having set stats and being unlocked fast (apparently you can get to level 10 in about 4 hours of online, last unlock is at level 20)
tenacity is a weird perk (fills specials faster depending on the team's playercount.) does this mean splatoon doesn't have to have a full room to start a match?
none of the perks seem immediately over powered or cheap, except for maybe haunt, but that depends on the amount of time shown and most people only really glance at the gamepad anyway. also, you can see the position of enemies in your ink if they walk into it on the gamepad, but nobody ever seemed to notice it. probably won't be that effective in practice, except maybe for competitive teams or higher level ranked matches where people remember to check the gamepad (quick edit: quick respawn may be the norm among competitive teams, probably the perk closest to borderline broken, although it'll probably only save you a second or two each time so won't be that big of a deal)
opening gambit is interesting. i wonder how that would work in conjunction with splatterhopping on rollouts. same with swim speed up. probably the most curious i am out of all the perks listed.
anyway, this is some really exciting stuff.