I'd like to suggest putting Red Cards into Familiar Point Shop, especially in Reboot where we are constantly grinding for familiars for a mere chance of getting Boss Damage, Ignore Enemy Defense, Large Item Drop, Item/Meso Acquisition, etc. I've open up over 26 Unique Ascendions and did not find any usable lines. When characters are over 270+, they don't train in Limina anymore, the prime place for familiars. The solution is to either invest in another character to grind for more familiars, or use their mains that could be training in higher level areas for more exp. While many could grind for more familiars, most of the popular maps are already taken in every channel to get more duplicates, which then forces people to either give up or reinvest in new familiars. I suggest putting in Red Cards in the shop because it would allow players to extract different familiars to invest in existing familiars, and so that the inventories aren't flooded with unusable Uniques. The shop itself is also very small: 300 points for familiar fuel or 2000 points for a chance of getting legacy familiars that no longer drop. It'd give the shop more functional use, and it'd make grinding familiars more worthwhile, especially when maps with specific mob familiars aren't always available. As for how much a Red Card should be, I'd say it should be worth 200 familiars worth of points since it takes 150 familiars to tier up an Epic to Unique.
That also being said, I'd also like to suggest implementing a bag to hold familiars, similar to 40 slot Recipe Bags and 40 slot Soul Bags, in the Familiar Point Shop. For the same reasons, familiars can take up a lot of Use space. While it doesn't have to be 40 slot, it'd be nice to have an area where all familiar cards can go into. I'd say the cost of it would be 500-1000 points.
Thank you for reading, I hope Nexon will consider implementing this change.