Gold mined is able to be spent right away and thus mining is a nice skill to have if you want to keep your soldiers from deserting you, not to mention study new skills. Once you have horses you will be able to travel faster and produce stronger forces. Horses can also be purchased in plains cities. Horses are a good thing to have if you want to get somewhere fast. If your orders go for more than 30 days they will wrap into the next turn's orders.
Several objectives are evident in the game, however most require some amount of money.
Also, try and determine a goal or direction for your faction. Are you going to be an explorer, a mystic, an empire builder, a master merchant or some combination. Don't try to do everything. Arrange to sell information that you have to other players, such as maps, lore sheets, trade routes, secret locations etc. A skill under Stealth that allows a noble to earn between 50 and 150 gold once per month while in a city.