Hi, actually when I start my second Splinterlands account I did it from the ground, no investment more than the spell book. I won't say it was easy but like you I had a bit of luck and I could had some credit from my first chest reward.
I would advise you to rent first rather than buy any card just yet, once you're advanced a bit in the game with a bit more credit or DEC or money you can buy cards.
Good Luck.