If you like to turtle and sim-city then I would suggest Australia to start. Has good adjacency bonuses for any style you want to play (science, commercial, culture, religion); civ ability lets you build massive cities (land-area and population); outback stations let your cities keep growing and producing; and the leader ability lends itself to a defensive playstyle (100% production after a declaration of war means if you need to build an army quickly you can). Objectively speaking, they are probably a pretty overpowered civ - especially if you can get a couple of high-adjacency holy sites and take Work Ethic, your production and faith economy will be nuts - but I find them a lot of fun to play with. Even their UU, which is the weakest part of their kit, is fun to mess with if you want to go conquering abroad late game or just use them to liberate some cities for the production bonus.