Year 1 Promos are available for purchase (e.g. Amazon) with alternate artwork. Presumably the same will happen with year 2 promos at some point. I think it's fairly safe to assume they will release the other content at some point as well, no idea on time frame.
Off the beaten path, I've played Binary Homeworlds for another nice space-theme 2p dueling game.
The key thing is what qualities of Star Realms are appealing. The length? The mechanics? The theme?
I'm using the recently released box set
I tossed the insert and made my own dividers from foam core. Picture here
I fit a good amount, base set, colony wars, frontiers, all of crisis, united and high alert, 6 commander decks, and the first gambit set.
I used this one. Fits every Star Realms card in the official sleeves on one side of the box with room to spare. I haven't opened Hero Realms yet to see how much room that will take.
https://www.amazon.com/dp/B00XJI0WAS/ref=cm_sw_r_cp_api_OcdrybSTX4349
Thanks a lot! I figured out a few of those things (early trade, scrap early/often). The rest will take some practice to understand more fully.
In case it helps others, I've enjoyed KeepScore on Android for keeping track of Authority levels.