Having suffered more than two dozen cross-planet raids (CPR) in my current game, I now see that the first one is the worst (better: the first IV one): once you survive that one, the rest is more of the same. They should somehow become worse and worse over time.
- CPRs should not always select the "closest" human planet. Occasionally they may select a more distant human border planet (or even an interior human planet)
- CPRs should become bigger over time (I think they are now only becoming more frequent as the AI progression increases)
- distant CPRs should sometimes grab ships from planets they move through. If that planet has no Orbital anymore, they should always grab all ships
- the enemy should start synchronising CPRs after a while (after e.g. 10 CPRs, whenever an CPR is generated, the enemy has a x% chance of releasing a CPRs from another planet that is close to generating a CPR, x slowly increasing, and after a while a third may be generated)
- after n CPRs, the enemy will stop normal raids add the raiding ships to a planet nearing CPR (once you have survived a CPR, normal raids are swatted like flies)