What could be better in my game?

Well, guys, I really love RTS games just like the Epic War series and so I decided to create such a game by myself. Then Gods' Fall was born. I've added to the game things I missed in other RTS games, so I was expecting that people would really like it. The game was published in Newgrounds and Scirra Arcade and it looks like people didn't really like it. The game has 3 stars on newgrounds (of more than 100 votes) and something like 4,5 stars in scirra (of 2 votes). But almost no one give feedbacks telling what is wrong with the game and it is frustrating because I really want to give people a good RTS for them to spend lots of hours playing for free in the browser.

Now that you guys knows the history I would like you to help me finding what makes the game boring or few interesting. Don't be ashamed of telling the truth, I'm really expecting this from you. So thank since now.

The link of the game in Newgrounds is down here, please rate it if you can :D

newgrounds.com/portal/view/726586

It needs a better tutorial. The way that tons of information is thrown at you is annoying, I start the first level and get introduced to every menu all at once. You can't really expect a player to jump into the gameplay and instantly know what everything does, better designed if you guide them through it. The information for all those circle icons was ridiculous. The first castle has too much health as well, very tedious.