Been playing Sins since it came out. There are a few things I would love to see in the expansion. I will try to keep these wishes in the land of fisability (I would love to have the ability, for example, to ram any ship with any ship; ie, suicide the firgate into a captial ship for high damage... but I know this would be a beast to impliment and would WAY overdo the micromanagement in the game. Also, as cool as they would be, boarding actions would be too much to ask for for the same reasons)
- When a captial ship dies, make it a truely cataclysmic event. Have the thing go into a 10-second death throw and culminate with either a major break up of the ship or, and make this a random chance, an explosion that deals some real damage in a small radius (enough to be fairly damaging to frigates and noticable to curisers).
- Planetary Assaults. Make this a sort of off-screen affair. Something like a defense value for the planet based on fortifications, population, climate and ground forces purchased on the planet. The attacker tries to beat this value by lowering it with bombardment (ie, the damage dealt to planet HP and population as well as damage vs ground forces) and assaulting the planet with a troop ship Cruiser that visibly is sending down pods, transports, supply shuttles, etc. The more invovled, the higher the attacker's rating is (and destorying these in space combat lowers the rating obviously). Once the attacker surpases the defender's rating, a sort of countdown begins as the defense rating beings to slowly fall. Once, say, a minute or two goes by, the planet is captured and you get all the surviving population and infrastructure. This opens up new areas of reserach as well, as you now have to reseach the new Crusier AND some races will have research that increases the effectivness of planetary defenses and assault forces. Also, have culture play a role in how quickly an assault succeds.
- Planetary Defense Weapons. Allow each race to build some kind of weapon system on the surface of the planet that can fire out into low orbit (where ships bombard them from), thus allowing the planet to defend itself. Beam weapons, rail guns, and missle batteries are all ideas.
- New special planet traits to discover with exploration. Maybe try to have every planet have at least one of these, to make exploration more worth the trouble.
- Moons. Lots of people ask for them and I have to agree. Allow moons to support one special structure than can only be built on a moon, such as a colony (increase pop and thus credit income), mining opperations (provides double the metal or cystal an ateriod does OR maybe even the same amount an asteriod does, but both resources), defensive weapons (like Planetary Defense Weapons, above), research base (Civil or Military, you choose when you build it; it also increase research time by 2%-5% to make it better than the standard orbital one). The possibilites are really endless here.
- Capital Ship Upgrades. In Sins the Capital Ships are like the heroes in Warcraft III and Heroes of Might and Magic V. They gain Xp, level up and gain skills. What are they missing? Special gear only they can benefit from. Enter upgrades. You would have to build a special kind of lab to research these items and then bring the capital ship in range to upgrade it OR you could research these items at the captial ship shipyard and bring the ship in range of the shipyard to buy it the upgrade. Make it so at every odd level the ship can support a new upgrade (1 at level one, 2 at level 3, 3 at level five, etc). Ideas for upgrades include more powerful engines (move faster), a more powerful reactor (generates anitmater faster and can store more), increased armor, a more powerful shield generator, superstructure upgrade (more HP), and weapons upgrades (ie, long barrel autoguns, larger beam capacitors, etc). These traits are usually increased by regular research, but a capital ship can go far beyond that and has the space for some additional gear. Some upgrades can give the ship a new skill to use in combat, for instance, or even grant it some utility function, such as an on-the-spot regen for 10 seconds thanks to incredible damage control.
These are just a few of the things I've come up with.