I also invested during the FOMO season. I even bought packs, even though a lot are advising to build our deck first, hoping that I would get a GF legendary. 😁
I also saved almost all of my reward cards and I am now holding a 50k Power deck of cards.
!1UP
I think buying the packs were more advantageous because if you were intending to play, then definitely you'll need all the cards that are inside the pack, this was another way which I built my deck though.
50k CL is amazing, which league are you currently playing in?
I used to play the Modern Gold III League.
Currently out of the battle field the whole season renting my cards trying to build up my summoners. 😊