@UnseatedDonkey: This inventory is - in my opinion - a good idea. Then you got a good overview of all you got.
Especially the evolution stones for the dragons would be great. Others like black pearls, elements for the flaks, ice and fire shards would be very good, too.
@Fairyknight1: I know that every second level the necessary items are displayed. But you don’t know if there are the necessary number in your inventory if the tower hasn’t the “right” level. And this is what I want to know. Because in events you can get these items (I mean, when I’m out of sigils for ending the dragon, I choose a smaller way to get the best out of the rest of my sigils, maybe I can get some fire or ice shards, but only one of them with my actual sigils), but you don’t see your actual number and that means you can’t realy predict what you could do in the next fortification.
The list in your link is good - but I hope that there will be a list in the game, too. Or a display when upgrading the tower, next to the needed lumber/food or whatever you need and the duration of the construction time.