This is a solid plan. Stocking up on GFL that other players will want to rent is pretty genius. It goes along with selling picks and shovels during the gold rush. Plus everyone pretty much understands how Gold Foil Legendary why they would be a value to any player.
In the past the only way to earn playing video games was to refer people to play. For the person refered their only upside is a little fun. With Splinterlands the upside is a little fun, plus a little income, plus investment opporunities for more income.
I only just started to understand the real value and power of Index this past week. Interestingly enough that is also when I started fgetting into Splinterlands as well.
We're hoping, down the road, INDEX just isn't a little income for people, but a solid passive income source :)