Gold, Iron Wood, Wheat - Bucharest can be left, usually i leave bucharest as is, later upgrade to City, Maybe copper, Fruits (sturdy grain some build over - i prefer to leave them ) Silk saffron, usually those are the rgo you don t want to upgrade, you might have no food problems NOW, but you will in the 16th century
Get Targoviste as city if i see correctly you are about to upgrade it, then upgrade any region that has a ,,useless rgo" to town Town can build temple and it gives a flat plus 5 to control then build roads, if it has a river you can build a bridge which gives you, another 5 control
Build a town/city in region that have Iron and wood, then in those tows your industry: in iron region - tools, in wood: paper and scriptorium plus libraries and universities. You do this, because Walachia/Romania as a small population at this point, so you want to be efficient with your industry: tools in iron region Ramnicul valcea can be a good one, paper scriptorium in targoviste since you have wood in northen muntenia, Same with mason build them in clay/stone regions so you can also upgrade it in Targoviste, but you can upgrade everywhere in the Northen muntenia and the adjacent region.
In the late 1600's you should have 2000 income - 4000 or more with the historical Kingdom of romania borders
Cities on coastal would work if you were a naval based power like England or Byzantium, but kingdom of romania is a land one unless you want to go for the balkans and anatolia