Icons, Terrain, Images, Background, Color schemes, Fonts, Videos, ... Important: license agreement, "raw" data
Fill in the big gaps, detail as much as possible. Results will be discussed first and then included in the game design document.
A nice 2D map using Qt features, possibly with procedurally generated look to avoid too much repetition.
The trading algorithms on multiple marketplaces, the setting of buying/selling goals, the actual trading, the influence on market share and balance sheet.
The tactic battle map and commanding armies on the battle map, conducting a single battle including graphics, user interface and computer opponents.
The goals to be implemented by each version.
The creation and implementation in the code of music and sound effects.