Here are some ideas I would like to see in Dragon City.
This is a long post.
Rune Tower Dragon-
Speeds up Summoning by 6 hours
Future Tower Dragon-
Speed up Empowering by 6 hours
Moon Tower Dragon-
Speeds up recalling by 6 hours
I would add towers to premium islands, but you don't have to build them. They could come with the purchase, and be quality of life towers worth the money.
Once a week skip Dragon Rescue cooldowns
Once a day 100 Event tokens or 1 heroic/progressive item
Refill League battles once a week
That new island Tower-
Speed up quest cooldowns by 6 hours
Upgrades to Tree of Life-
I know many people would like this. It speaks for itself, multiple slots for each action.
Upgrades to Training Center-
Imagine training multiple dragons at once...
Upgrade Ancient element habitats to level 7 and add tokens for these. You could then stash your ancients in less habitats.