New layout

sadly, there is no option of rearranging like we have it in clash of clans. youll have to manually do it by placing all the buildings on one side and commercial buildings on the other. yes the happiness goes down while you're rearranging but it will be back as soon as youre done. 

Also put all of your items like parks, landscape etc into storage to give you more room to redesign, bulldoze your roads and put anything else you have into storage too.