I am trying to max out my current town hall level before i need to move to the the next town hall level and I feel like it would be cool to have a side tap that would inform you on what's left for you to update. I mean I know I could tap on every defense and barrack to see what I need to upgrade but I just think it would be a cool idea.
Every building's level have a different looks or designs based on its level so you can determined a building if you can upgrade it just by looking to it.