It could be problematic but as long as the devs keep it as a rare gacha that only takes your gems after you Keep a Knight then it should be fine. Admittedly I did find myself a bit tempted to keep rolling after I landed Saffron as my second 6* outcome though. It wouldn't have cost additional gems to do so and at the time I figured that if I kept going then I'd eventually land an old favorite like Cactus, Acacia, Jersey Cudweed or Kerria.

Plus, all of the rerolls I did helped me learn that Cape Jasmine doesn't have a RG form yet so I can be in less of a hurry to reassemble the Four Heavenly Queens of Drinking.