A word of advice from an average of bad pvp casual, just get as close to 7 wins as you can for now, then wait and come back and grind a bunch at 7 wins after Sunday reset when the flawless pool activates. I did that for a few weeks and got a bunch of engrams and golfballs.
Only thing to keep in mind, even after the flawless pool activates, if you play solo you will probably get smashed for a few games, but then you get guaranteed an easier matchup. So I was winning 1 out of about 3 or 4 matches. That's still a golfball and or engrams every 30 minutes or so, about the same as GMs.
That sounds like insanely unlucky matchmaking, but isn't too surprising. Still sucks though! I got to 6 wins playing solo at 4 am yesterday morning, horrible time to play, and yeah I would get stomped 5-0 against a flawless 3 stack maybe 4 or 5 times before I would get matched against solos on my level, then get a win.