When it comes down to end game, and sometimes players are isolated on different planets, it seems like it's a never ending stalemate. Will there be like and orbital drop ship so more than one unit can move planets at a time?
There are many upcoming options for moving multiple units between planets upcoming, but the specifics are unknown. These include the Unit cannon that can shoot down from a moon, or as to my knowledge can shoot from low mass worlds to high mass ones as long as they are orbiting a planet. Inter-moon shots are unconfirmed. And the StarGate is a teleporter of unlimited range, but require receiver gates to send units through.
from what's been said I believe the inter-orbital endgame will consist mostly of utilizing asteroids, either for Annihilation or as invasion fortresses. once an asteroid enters orbit around a hostile planet, battle can commence between it and the planet using nukes, unit cannons, and possibly stargates. my main concern is that if you control a planet utterly, you could load it up with 20 nukes and no conceivable asteroid fortress could anti-nuke enough to protect itself. The only solution that comes to mind is an orbital anti nuke unit.
Id like to think that nukes would have more counters in exchange for becoming more common, kinda like a type of T3 bomber in a sense.
I see you're new here, and welcome! You should do a search before posting. Orbital is way under developed right now and will be receiving many updates to enable planetary invasions. Right now we only know for sure of Teleporters and the Unit Cannon. Though there will likely be some sort of drop pod. I'd encourage you to do some searching on the discussion on how to improve Orbital. You should check out this thread: https://forums.uberent.com/threads/planetary-invasions.54449/
Honestly, just try to avoid multi planet matches. And the idea of not being able to anti-nuke enough is reasonable. If you totally lost the main planet, what do you expect? Not enough eco, but this should be fixed/improved later on.