1. Follow the storm8 model for the strike list, the current model is senseless, useless, and ridiculous.
2. Make alliances more important, create alliance banks that fund alliance forces. Also introduce tournaments where gold can be won, and the gold reward when a clan levels up in prestige should be equal to the new prestige level.
3. Reduce the price of gold units by 20 for all of them. According to my calculations a player will need to spend a bare minimum of US$400-500 on gold units for them to count for anything in battles. For them to make a significant difference US$1000-1200 is needed. Gold players already pay about US$50 per month for ammo refills, so the cost adds up. If players see a marked increase in their strength from spending say, $100 dollars on units, they will be encouraged to spend more, widening your paying user base. (Monetary costs assume that players buy the $100 gold bundle only)
4. Charge gold to further customize player and alliance profiles. Vanity items can also be added. (The country flags are in effect a vanity item). You can also charge players gold to talk in the world chat/alliance chat, players that don't pay should have their messages capped on a per day basis. These raise money for you without inbalancing the game.
5. Allow players to re-spec their account (tactic points, skill points) for a small gold fee, small enough for non-paying players to buy it too. 70gold maybe? To avoid abuse of this, this option should only be avalible for a week in every 2 months.
6. Appoint player moderators who can gauge interest in planned game updates, and also silence people who use excessively inappropriate language, misuse feedback wall, spam messages etc.
7. Add a whisper function to user's walls. This will reduce the incidence of illegal activities over palringo or kik.