Personally I believe you should reduce the cost of many items in the shop. The prices are just way to high on certain items.
My main issue with the game is the emporia mechanics, they in theory should balance the game for users who cannot afford to spend too much, but in reality they are just killing fields for troops. What about introducing a timed period where the player can gather without being attacked?
I like the guardians but to make the highest guardians only available to people who spend money is wrong in my opinion. Players should be rewarded for their dedication to the game and community not the size of their credit card!
The more you'll make your games unbalanced between spenders and non spenders the more you'll kill the interest in it, plus your going completely against the trend, "league of legend", "dota" etc.. Those games are entirely free to play if you spend money it's only for things which do not affect gameplay and the user base spend a lot to get the latest costumes for their hero etc. But what do they know with only 35 millions of monthly unique users!
Here's a classic example of what is wrong with your game:
New player spend two weeks on your game reach level 40, pretty much minding his own business happy to growth his little city, one day he or her decide to raid a siege of a big player, O dear now a level 98 his coming to pay him a visit "coz don't touch my farm boy" result new player naively put his defence out only to be wiped out by 50 millions worth of offence. Guess what new player dump the game. Why? Because he quickly realise the game is unfair, any decent online competitive game has a ranking system so big players cannot come near newbies. What you did with your game balance is letting Garry Kasparov with an unlimited credit card play chess vs Bob our newbie who has a budget of $10 a week for his online gaming!
You seem to be more focused in creating new skins for your games than fixing the mechanics of it. What I mean is Vikings, fantasy, Sparta etc... it's just the same game over and over, just new gfx, what's next dinosaurs!!
Ok enough renting after all you wanted some suggestions, here's a few.
1. in game bug reporting system with screenshot.
2. Building skins and troops uniforms colours, troop flags something so the player can make their troops and city unique and have fun doing it everything just cosmetic no stats change, décor for the city which cost nothing and does nothing just purely to make it pretty and fun so we don't all have the same sad city with the same crap in it!
3. Big raid warning in the middle of your screen with sound alert. So when your doing something in another part of the game you don't get annoyed to not be able to defend your city even if your sitting in front of your pc for the last 3 hours coz you missed the tiny little icon that you couldn't see!!
4. Easy troops management, let the player decide in which order they display, I mean infantry at the bottom come on guys we use the jav the most!
5. Change the limits on coalition cooperation what's the point of sending 50k of grain to another player which is level 100 barely a snack for him. The limits should be a percentage of what they can hold or produce daily. Something which make sense.
6. Change the rewards in "Spartan Allegiance" those are outdated and insulting to any players who log in daily. example "day2" 2 hoplite "day32" 2 hoplite!! lol come on did Mr scrooge did it for you.
7. Give players random rewards for nothing many other games do that especially if they have left the game for a while. "bring those addicts back"
8. Fix Leonidas city it look just like any other average player city and he's supposed to be a bad ass!
9. Give us a building who produce drachmas not much very slow but at least after a week we can buy our self something in the market and feel good about our self.
10. Make the unique units only available in paying money available to all to produce.
11. Give us fleet so we can sink each other galleys or steal their transfer of resources or something like that, balanced it make it fun, I WANT A BATTLESHIP!! I'm kidding.
12. Overall make your games more fun instead of consistently focusing on how can we make them spend money. If your games are well balanced and fun to play users will be more willing to spend. At present you look like a money obsess company who doesn't care much for it's customer base and with a weird logic. example every 2 weeks you give us 75% revival but what do you do, you cut down the package we can buy on that day. It's just dumb you should have loads of offer on that day so we can all kill each other spend some money do it again and again should be ww3 out there on 75% revival day!!!
13. If you use any of my ideas "I WANT TO BE PAID IN GRAIN!!!!"
I hope there is something you can use in all my verbal diarrhoea, if not never mind.