The good news is that the holy city will require one national wonder, the Wall Street, for optimal use and this does not conflict with putting the Heroic Epic here (short term) or the Ironworks (long term). Bad news is that it prevents you from combining two national wonders (out of Ironworks, Heroic Epic, and West Point) for a super-production city. My advice: you don't get many holy cities, but you can always found other production cities later. Once you get the shrine, use this city for some gold, by spreading the religion and getting market, grocer, bank, and Wall Street. You can still use it as a secondary production city and find a better Ironworks cite later.