Ok these are the two things I have been thinking about lately. What do you think? Would they be fun?
NPC Invasion system
This system could replace the deep space encounters and would add to the fleet action repertoire and would also make sense on a conceptual level since the Feds and the Klingons are at war.
On a basic level, NPC invasion forces spawn (one at a time) on the borders of a sector map on a regular basis (more frequently in peak hours and less frequently – or not at all – when few people are playing). On the other hand, the spawning could be mixed-up more so one hour there is virtually no invasions and the other hour there is a massive co-ordinated invasion (multiple simultanious invasions) that attempt to take over a whole sector.
These invasion forces head for the nearest enemy star system and if they reach it, that system will convert to whatever faction the invasion forces represent: no missions or areas can be accessed in that system until the invasion force is destroyed there (so it's a pretty good reason, besides the xp and loot, for players to get together and destroy them asap). Invasion forces can be attacked en route to their destination (deep space encounters) so they can be prevented from taking over systems.
If an invasion force has taken over a system, players can enter the „defeat invasion force” mission there. The invaders will represent a considerable force and the mission will require many ships (a la fleet actions) to be beaten. If the system is cleared it will return to its normal state (offering the missions or areas that it did before the invasion).
If the invasion force is not cleared, (after a set amount of time) the paricular system that has been captured will spawn new invasion forces on the sector map regularly (in addition to the basic spawning at the borders).
An automatic, faction-wide notice will be sent when invasion forces are detected in a sector and when they take over systems.
Open war zone
Basically a new sector where Federation players can attack KDF players freely. There would be some space stations/systems in that sector that could be sieged and captured and would provide some benefits for the faction that holds them. E.g.: let's say there are 5 systems total in the Open war zone. If 3 out of 5 systems are captured by one of the factions, that faction will receive a +50% xp boost for one hour and a 10% xp boost after that hour until they loose one system. Occasionally a third NPC faction (Romulans) could attack some of those systems and attempt to take them over to make things more interesting.