The game has come so far since I first played it. Still enjoying the game with one major exception..... VILLAGERS HAVE A DEATH WISH!! I am going to try and give you the experience you have created from the gamers perspective so you know how painful this issue is and why you really want to fix it ASAP.
In the end game when you have over 400 villagers having 20 or so burn, freeze and otherwise kill themselves at the main entrance to your defenses might seem funny at first but I assure you as the player is is nothing but infuriating. Every night and they won't stop running out like the stupid lemmings they are. What is the point of leveling them or even caring? Thankfully late game allows larger amounts of nomads to come and replenish your lemming supply. Oh and they are low level they are even more useless yeah! Woo are we having fun yet? Not me. Every night I get to look forward to the same stupidity. I guess I could de-list all jobs every night and micromanage everything to death. Wooo even more fun woot woot (heavy sarcasm)!
Stop it. Stop stop stop stop stop. Stop the villagers going out at night and dying!
Games need some degree of control otherwise they are not fun. Spamming recall ever 10 seconds and wasting the associated mana and being stuck at the main gate every 10 seconds for an entire night that drags on for 10 minutes IS NOT FUN!
PLEASE consider something that directs workers away from an area or stop them from being lemmings. If I wanted to play lemmings I would and that game has great game mechanics from making sure you can keep the little idiots alive.
At dusk and night having villagers stay 50-100 or so tiles away from any monster would be a good start. Consider the end game when monsters easily spawn lv 90 so all villagers do is die if they encounter a mob. I don't care if it is a god power that repels them or if I can keep them within the area of the castle or if there is a way to lock gates to keep them from leaving. Anything is better that than this current disaster. Many of the issues come from them wanting to repair a road outside the main entrance or gathering something dropped or other such nonsense. That means there is also a low level death count during the day but that is only 3-5 per day which isn't so bad.
Other than that issue you have nailed the major lag issues and put some great polish on the game. I would love to see it be even more successful in the future.