At least 1v1 isn't an Advent smurf/rushfest like all the other ICO games. Can the other factions even rush any more?
It isn't a rushfest, but 1v1 your opponent will still choose advent 90% of the time. I know because I have quit playing in the larger games for my own personal reasons, and pretty much do 1v1.
To give you a taste of the dilemna I faced in my last game, the game starts. Because I am still paranoid about having 2 halcyons show up early game loaded with bombers, I built 2 Sovas, dropped 2 civ labs, then started scouting and expanding.
I didn't start building any fleet right away, because in my opinion that's the kiss of death against advent. You have to see what HE's building first. I mean you oepn with a ton of lf, illums will come your way. You go lrm, you're gonna get hit with seekers, on and on. So I built production facilities, but otherwise waited to see what he was gonna come with.
Much to my chagrin, he came with... nothing! Then it became clear to me that his plan was indeed to wait for me to commit to a fleet, and then he'd react. Meanwhile, he would eco to the max, and start harassing my neutrals and asteroids with seeker/disciple attacks all over the map. If I came with nothing, he'd eventually tech to a late game advent. Time was on his side.
So once I discovered his plan, I moused over the eco. I was #2, even though I had chosen tec, expanded in two directions simultaneously, had not teched or built fleet, and had gotten trade ports established as soon as I reasonably could, with a 6 or 7 planet trade chain. So I sent him a message saying "Uhhh... it appears that I'm #2 in eco, even though I wasted no time in establishing it. You seem to have the strategic win already, if nothing else. GG." To which he responded "gg" and the game was over.
In checking the stats after the game, his credits per second were either double or triple mine (can't remember which). I said to myself "Jesus... so much for the myth of the 'sucky advent economy'."
Don't encourage Advent bias- don't play Quickstart.