Interesting about the pack and what it will contain, I could suggest that the things in the pack be sold separately but more expensive so you promote the sale of the pack.
On the other hand I would like to see if possible that you can experiment with the potions mixing them with each other, some mixtures will improve the effect others will slow it down but it will give some fun there.
well the things in the packs will be tradable shortly after so you'll be able to sell or buy whatever you like then!
Excelent
good suggestion on the 2nd one, but I think we'll do something with rarities instead like everything else. Where certain potions restore more mana at a higher rarity or elixirs last longer