I've completed all of the challenges, and am currently completing the few remaining objectives via relatively boring Solo Battles. While I await a new round of content, I have the following additional options:
• I can occasionally get winnable matchups in Champions, although I have very frequently faced off against overpowering lineups. At least that mode resets each week, and there are no long-term consequences to any one loss in the context of my actual skill and the week-long timeframe involved.
• H2H Seasons could be an alternative to Champions with a similar rationale.
• I can proceed with the Ultimate Solo Seasons. I have gone 8-0 thus far, but my defense has been worthless, and with my current lineup, I'm almost certain the next game will end in a loss.
• I am skipping Ranked H2H altogether until at least the first patch, because early losses against cheat plays will indeed result in negative long-term consequences.
It seems that the rewards for Champions are probably the best and most attainable of the lot for an NMS player like myself.
What are you focusing on as you await the first patch?