Haven't seen a post on this in a while, so thought I'd say my bit, see what you guys think.

So, through the diplomacy tab, you could declare war on other legions (this could be limited to others with +- 20% average rank to make it fairer for example)

Maybe with a minimum level threshold, like the legion missions, or that you can only declare war on legions with a base the same level as you

Then the following would happen:

Planets of the legion with which you are at war are flagged.
Members of the legion are more likely to show up on your bt (but you still won't have anyone you shouldn't on it)
Raids are more likely to kill crew members

Whilst at war, base production could increase, and have some faster AP regen to deal with sustained base combat. But also, the opposing legion doesn't need to lock to attack your base, its just a seperate option.

Alliances: perhaps through an installed base module, like the embassy, you could set up alliances.
This would stop allies from appearing on the bt (or lower the rate)
Flag the allied planets

There could be a diplomacy with regards to ending wars, e.g. Reparations in the form of giving away base payouts automatically.

Then there could be a new type of badge, awarded directly to the legion base for winning wars/base defences/base attacks etc.

They you could buy (as a legion):

Diplomacy Center: Allows 1 alliance to be made per center built

AP timer upgrade structure: reduces AP timer by 5%, can be upgraded

Telecommunications upgrade: Requires Base Comm Interlink - reduces planet alert/player alert timers by 5% whilst at war. Can be upgraded

Recource booster: Increases the availability of one base resource at randon (high cost)

Any thoughts (other than how unlikely it is this will happen and how hard itd be to program)

Nope