Thank you so much for such a detailed comment. You make a good point about the game's difficulty. I'm usually able to survive at least five minutes by rushing four archers around my king and then making a diamond shaped box. Early game a box with archers is king! (No pun intended)
We will tone down the spawning of the monsters and see if it helps. In a future update we will also have a system where the longer the archer and knight is alive, their 'rank' will increase. Giving them more health and attack power!
Again, thank you for your feedback and we will be looking at everything you've said. We are new to making games, so many of these things are not obvious to us. Have a good one!
EDIT: Archers can shoot over walls. Maybe I will make this clear in the instructions.