Let’s revisit this idea for a moment, because people are likely to suggest it again in the future. This would essentially just be a side feature, it doesn’t really seem like something with any real substance.
First of all, it would require that ground troopers have an AI to make them worth using. If they just move in a straight line, they’ll get easily picked out by players. Do note that in order to keep them balanced, they have to be useful enough to kill players, raid bases, etc, but weak enough that players would have to either be very ill-equipped or overwhelmed to be defeated. This essentially requires an AI to provide ground troopers tactics that make them competent enough at combat, which is not easy.
Second of all, it has no counterpart in space, nor on the home front (I have brought this up before). Ground troopers wouldn’t make any sense at all without a counterpart fighting space battles or working in factories at home, which requires even more complicated AI (not to mention that having a lot of AI pilots in a space battle would probably set your computer on fire). Neither ground troopers nor AI pilots would make any sense without workers at home who actually make the goods required to wage war. While automation certainly could take the place of workers, and it certainly has historically, without npc’s at home npc’s fighting in wars doesn’t make any sense. Logically, where would the combatants come from?
And third, it would be a challenge to make them worthwhile without making them OP. For this I will provide an example. During a completely hypothetical battle on Arbusto between Arimfea and Oblivion, Oblivion is being attacked. Arimfean dropships land on the surface and release 100 ground troopers. The ground troopers reach a certain point before getting mowed down by Oblivion’s defenses and (player) troopers. In a different province of Oblivion, no one competent at combat happens to be online, but there happens to be a lot of (npc) ground troopers. Arimfea lands 150 ground troopers, slightly less than the 160 at the nearly-undefended Oblivion province. Both armies nearly wipe each other out, wasting lots of time and whatever resources were used to spawn the ground troopers. The remaining Arimfean ground troopers are snuffed out when Oblivion brings a small squadron of npc and player ground troopers to the province. Arimfea’s invasion force realizes that using ground troopers to attack Oblivion is an absolute waste of time and resources, so they just straight up nuke the base from orbit and send a squad of (player) troopers to pick the remains clean.
As you can see here, in this hypothetical example a lot of ground troopers were wasted with no positive result. Now let’s imagine that ground troopers are OP now.
In an alternate example, Arimfea invades Oblivion just like before. They release a vast number of ground troopers on the surface, and they ravage the base with blaster cannons and thermals, avoiding enemy fire with a clever AI. The Oblivion base is devastated despite being probably one of the best-defended bases in the server. Now let’s return to the mostly-undefended province with the Arimfean and Oblivion armies clashing. Here we’d likely see a more interesting result, because making troopers OP basically is impossible without having an extremely powerful AI, making the results more variable. Here it would be much more interesting because the conditions for victory would be far more complicated and not solvable with pure math. However, when Oblivion (player) troopers get to the province to clean up remaining Arimfean npc forces, the Oblivion (player) troopers are obliterated by the cheap, mass-produced npc troopers.
The problem with the weak troopers is that they were useless. The problem with the strong troopers is that they overpowered top players and bases despite them being easy to mass-produce.
An ideal level of trooper strength would probably look like this version of our hypothetical battle:
Arimfea lands 100 ground troopers on Arbusto to invade Oblivion. The army does moderate damage to the defenses, softening them up for Arimfean (player) troopers to do most of the destruction. Most of the troopers have been killed, however, because of the remarkable defenses Oblivion has set up. In the end, the Arimfean (player) troopers siege the base, and the npc troopers mainly just softened them up for the real players to do most of the damage.
Now in our unguarded province scenario, the Arimfean and Oblivion armies clash in a realistic and logical way, with results that are hard to predict with simple mathematics, making them interesting. When Oblivion reinforcements arrive at the province, the remaining Arimfean (npc) troopers are cleaned up by the far-superior player-troopers.
This is what an ideal scenario would look like, provided there are AI pilots and npc factory workers at home to balance them in all areas. As you can see, the process of making them balanced is not simple and would take ages, and might not even be realistic in the first place because it might cause some major lag.