Suggestion: Keep them around after to keep the Favors valuable as well as the skins but increase the cost due to “Limted availability”.
There’s some nice skins in there and it would nice to be able to still attain them even if the associated cost of gold increases, similar to how BLT costs go up for Fused, Jade, Wintersday et.al. weapons or a Laurel or similar cost added after the Gauntlet was over.