Last year was my first year as well. First baseball game I've owned since Baseball Stars on NES in like 1990. You're not the only old [censored] in here.
I bought it late and then didn't even know there was an online marketplace or app until like the 4th inning. Eventually, I got every card but I should be more efficient this time.
Side note, Baseball Stars was an awesome game. You could build your team and it tracked stats. You earned currency on wins and could upgrade your players. Way ahead of it's time.