I've played on Aether flames (the highest win rate GC) and Aether adders (the lowest win rate GC) and it always feels like RNG is against the adders. However, this is only because the Aether adders tend to play passively and prefer to sit on nodes than to attack. You'll often have people snicker about how Mael and Flames are foolishly fighting each other, only to have the game end up horribly 10m later. I keep telling people that points don't matter early game, you can be ahead at something like 300/200/200, but when the late game kicks in and the opponents farmed a bunch of battle highs you'll never finish off the final 200 points before they run you over.

Only the last 200 points really matter, the early game should always be about farming battle highs and killing off opponents so they can't maintain their kill streaks. If you do that, the RNG is significantly reduced, as when the big boy nodes pop at the late game, a battle high heavy GC can waltz into whatever node they want and cap it, and then sweep whichever GC is leading and prevent them from capping anything. If you're GC doesn't have the pushing power at late game, you'll find that RNG will always be against you, as only 1/3 of the time would you get favourable nodes that you'll probably lose in the next minute, and 2/3 of the time the nodes will be near the other GCs that you'll never be able to take.