Win or lose, Nexus Blitz is unsatisfying
It's like a super extreme version of Mario Party, but without the careful design and balance. It's just a pile of crap thrown in so you can have a clown fiesta, but having a clown fiesta in a pile of crap isn't actually fun. The more I play this mode (to grind an "event" currency that'll get me a skin shard at most, after a month of daily chores... oh God I hope it's limited to a month), the more I see that it's not "gaming" in the way people who play computer and video games think of gaming, but rather the way the Nevada Gaming Commission thinks of gaming: a roll of the dice. I mean, there aren't even any mode-specific balance changes; it's just more stuff. More random Blitz grabs, more gold, more damage, more environmental damage (so fun getting executed right after winning the URF arena after getting several kills without dying, just because you have no sustain to counter the constant DoT... seriously, why does that need to be a thing; isn't there enough damage flying around? are people really playing hide and seek in the URF arena to the point that timed deaths are necessary?), more damage, less damage resistance, more mana regen, MORE DAMAGE, a shrinking ring of damage, a damaging sled, a damaging catapult... If a mode like this is going to be the focus of LoL from this point on, with extra rewards in missions and such, then in a few years LoL matches will comprise a bunch of explosions followed by an RNG "mechanic" that gives one team a win.
I feel bad for the actual Brand/Veigar/Yi mains, too, because they can basically never play their favorite champion in this mode.