I'm not sure what I'm doing wrong, but I can't get past 12-15 population. I always remain without useful cards. In the last run, I had a bunch of remove cards and lumberyards, bot no trees on the map. Maybe if there was a way to access more cards, that I have previously unlocked, the gameplay wouldn't feel so random for me. Or maybe I just suck at playing it :)) since there aren't explicit instructions anywhere :( But otherwise, this looks great, I like the concept and the visuals, and interactions are very satisfying.
Start of this game is very RNG brutal, but you can get a decent start with rocks if you just use remove cards to them (generally not advisable to erase resources). Typical pattern for games by population goes like this: 10, 28, 16, 34, 12, 78, 18, 12, 134 (2 castle parts), 18, 18, 24, 64, 14, 104, 224 (with 3 castle parts and 4th in the deck), 16, 34...
Still, It feels almost mundane to finally get demo "completed" with 4th castle part. Usually that happens between 170-280 pop. When that has achieved, you need typically over 1000 population more to reach a situation where a deck size (and RNG factors related to the deck size) allow you to really transfer to 'a perpetual mode': i.e. to risk of losing to a bad hand diminishes, being smaller and smaller.
Key lesson: Try to arrange your map such way that you get a situation where you can always play all cards, regardless of what you may get on your hand, and continue to build your map such way that you ever-increase that buffer. Immediate optimization of a play of individual card isn't necessarily same as longer-term optimal. You try reduce the impact of RNG as small as possible. After some 1.5K pop. most important thing is to be ready to handle with intense lags: Let game do what it needs to do after every action without buffering game with more hasty actions. It gets very time consuming...