That was years ago bro. If you were playing actively during the beginning of the citizen experiment, you should have turned all your single population citizen cards into sick citizens to access the +3 tax refund that was being maxed. Plenty of developments since then have extended the games economic lifecycle including the minimum sick citizen tax refund. I have been playing for a few years now, so I know exactly what you are talking about. You can delegate 500 HP for a daily free citizen and ofc you already know about claiming the leaderboard. There are also plans to implement a new citizen claim for certain buildings on the next update. If you haven't looked into the max tax refund available from your building combines you may be surprised.