There is already a suggestion for this, you can find it here and upvote it. The Devs for this game are great in that if you post suggestions and they get enough upvotes it is likely they will incorporate them into future updates, but they have to be in the Feedback-Suggestions area of the website, but if you post them here on the forums it's much harder for the devs to see and for people to get behind and upvote your idea so it's not as productive.
There is already a suggestion for this, you can find it here and upvote it. The Devs for this game are great in that if you post suggestions and they get enough upvotes it is likely they will incorporate them into future updates, but they have to be in the Feedback-Suggestions area of the website, but if you post them here on the forums it's much harder for the devs to see and for people to get behind and upvote your idea so it's not as productive.