Thank you, I really appreciate your comment :)
Feedback, positive or negative, is always welcome to keep improving.
1) You can drag by pressing middle mouse. I tried to enable right mouse button as well, but it is already used for deselection. The game has to decide if the player wants to drag or to deselect, by a little timeout, e.g. Solving it seemed to mess up the controls and caused a stuttering game flow.
2) Good idea. In fact the player gathers more money than he can spend. The game needs rebalancing and different modes.