Eiffel tower at night
Churches, mosques, temples - whatever wonder of religious architecture interior you have nearby
Take more train terminals, power stations, stadiums, soldiers, water towers, metro station, prisons, bridges, airports, presidential palace photos for dat urban industrial vibe
Go to developed and overpopulated countries like Sweden, Denmark, Norway, Germany, France, Korea for quirky street shots and candid portraits
Nature pics of Australia/NZ is basically cheating in photography
Get free nude models in naturist beaches
Go somewhere exclusive and take pictures that everybody would be envious about - Sistine Chapel in IItaly, architecture in Latvia, any of leader statues in DPRK, Lenin's mausoleum, or at least do urban exploration in your city
If Iceland/norway/scotland is too expensive for you, you can always go for much cheaper and off-the-beaten-path Moldova/Slovakia/Belarus/Ukraine/Poland