Their is a suggestion at the end of this rant.
1. Game is too team oriented.
Sorry, but nobody new is going to join the game when you can't accomplish anything yourself. Whats the point of playing a game that requires you to have 20+ active team mates at all times? Even in WOW you can do things without a consistent group of team mates. In utopia? Can't do anything except train troops and research science. And now that good players are all congregated in the same KDs, you have basically killed the chance for any new KDs to form (2 old longstanding kingdoms merging into 1 doesn't count).
2. Relations system encourages people to snap quit.
You need to get rid of the relation system you have entirely. You need to replace it with a 'que' like every other game has already figured out. You want to war? You enter a que and are matched with KDs to within a certain % of your NW. Sorry, but I know more people who have quit this game because of long stupid hostiles, and weeks of farming (on both sides of it), than I know people still playing. your system encourages cowardly behavior - only wave those you know you can beat. Simply idiotic.
3. Only 1 KD play style is valid
KDs have to be set up to give and receive waves. No longer is it possible to be peaceful, mind your own business, and grow. Why? Because a while ago some idiot thought it would be a great idea to let offense scale at a much higher rate than defense. What happened? The birth of all hyper aggressive KDs, which causes stagnation, which causes boredom. The only acres being explored into the game are by banks in about 10 KDs and that dries up fairly quickly because of your stupid explore pool. You guys decided that hey, lets only let hyper active agressive attacking KDs be successful, because that is 'how the game is meant to be played'. You took far too much strategy out of the game. The is no sliding scale of benefit in terms of speed of growth vs safety of growth.. now none of it is safe and its basically a giant purposeless crap shoot about who attacks who, and when.
Solution:
Remove relations system in favor of a que as described above.
Bring back unbreakable provinces: Value offense and defensive points at the same NW. Let generals give bonuses when they are home. Have the best defensive unit not be 2 points lower than the best offensive unit. Remove explore pool so that the game doesn't stagnate and people who don't want to be hyper active can still have a pleasant experience where they actually yield some results. New players especially don't like to attack and if you don't give them a chance to learn some of the more basic features of the game with some casual exploring ages, then they don't last more then a few attacks received. In addition, players who are now much better than the rest of their KD don't have an automatic reason to instantly leave. Why the heck would I waste my time trying to build up some ghetto when my province is going to get crapped on all age because my team mates can't back me up?