Heroes 5.5 WarGame Edition - Tactical Edition.

Overall, it makes sense, because this game depends on how the hero develops, and the castle as well. However, if you increase the cost and strengthen the dragons, they will be available for hiring, but there will be a choice: either a dragon or half of the income. In general, if you spend 2k gold per day and save another 2k, you will accumulate 14k per week (I adhere to a similar tactic, so these are the figures). If you set the cost of a dragon within this amount, there will be a relative balance. Of course, when the castle is upgraded, there will be more money, but, as practice shows, by that time either there are already a few more, or there is a lot of money and everything is moving towards the completion of the map.