Callumous has a very good point and your answer is a bit off-topic.
His/her concern is balancing the game so that the amount you spend beyond a certain point has a diminishing return on results. If the link between how much you spend and how well you do in the game is too strong most players who spend moderate to low amounts on the game will quit. Plarium will be left with a handful of elite players who have no spending limits.
I witnessed this first hand recently... an unnamed player was raiding and besieging a mid-level player in our coalition. Several higher level players came to his rescue and soundly defeated the scoundrel with a defensive ambush and raids destroying over 300 champions and many thousands of Promachos and Agemas. The villain immediately reappeared with a larger army which we again defeated with clever tactics but to no avail as he immediately revived it again and returned... this pattern repeated itself a few more times until our forces were depleted and since we are moderate spenders we could not just buy ourselves out of this. We defeated him soundly on the field but he just purchased a win from Plarium.
yes, the game would be better off if combat stayed fair and give coiners option to be stronger without too large advantage.
Overall i don't see this game lasting longterm, we want to have fun playing a game, not spend coin.
The most succesfull games try to be fair, as without a playerbase your kinda screwed. Without people to play with, cities to raid, people to fight.
Once people start using their brain and realise its not worth spending money on a game. Its way overpriced, for a simple browsergame.
No suprise that im raiding coiner cities all day since all things come to an end.