The Mintek fighter battle was brutal.
I didn't quite understand if the Mintek recommendations involve adding fighters to the warp point defenses or if they are going to be based at the homeworld.
You didn't understand because I didn't mention it <G>. Neeron's recommendations were made from the point of view of supporting the fleet. For system defense, the Mintek currently have a large, 257 space asteroid fort (almost as big as two superdreadnoughts) at the warp point. This fort has thirty fighters, three armed pinnaces, and capital missile launchers. In addition, the latest version of their BS5 warp point defense base will have a small fighter complement as well. Although it will take some time to refit all of those monsters. The Mintek have plans to build a second asteroid fort to be placed in orbit over their home world, to defend the planet against anything that gets past the warp point defenses.
With respect to ground combat, I hadn't considered the problem of orbital bombardment weapons causing planetary surrender. In Steve's writing the standard procedure is to ignore missile bombardment and start with beam bombardment to clear out beam STOs on the planet, then bring in ground units to take control of the surface.
I don't think I've seen any write ups of Aurora where planets surrender rather than face missile bombardment, but that might be partly due to the NPR AI.
Aurora is a different game, with different assumptions. In Starfire, there has been a long standing debate on planetary defenses. In Starfire, once a defending fleet has been forced to retreat, a planetary population is left with only its defenses to prevent invasion or catastrophic bombardment. Those defenses can be, in order, orbital fortresses, Planetary Defense Centers (PDC's), and troops. The orbital defenses and PDC's are armed with the same weapons that a fleet is, and so have the same advantages and disadvantages that the fleet does. In Starfire, weapons range is critical, nowhere more so than with planetary defenses. Your big, expensive bases or PDC's become mere targets if the enemy fleet outranges their weapons, and yet, typically, players will refit their fleet with the latest weaponry first, only later refitting defenses, if ever. Also, PDC's present a particular problem. To engage the PDC's, a fleet will necessarily have to bombard the planet, and there will be collateral damage to the population. A PDC on the surface of an inhabited world invites planetary bombardment. Indeed, David Weber's Terran Federation, the main human race in the Starfire source material, refuses to build PDC's on inhabited planets for that very reason. Better to have the planetary population surrender undamaged, to be retaken later, than suffer catastrophic bombardment. Indeed, there are rules for that.
I did think up a system for adding point defence fortification to planets (which you could track with excel or pen and paper) but I realised afterwards that once the defences are overcome the planet still has the same choice, keep up resistance despite the consequences or surrender. This again renders the ground forces somewhat moot.
The way to change the surrender calculation would require missiles (and probably all other weapons) to be less powerful vs populations, so that a fleet can't inflict a completely devastating amounts of damage once it has control of local space. This might be somewhat difficult to explain in universe given the events which have already happened, although I don't see why you couldn't implement it in a future campaign.
I've put the point defence fortification system below in case you are interested in implementing it.
In Aurora C# to protect a colony from missiles you want point defence STOs. With enough point defence the attacker can't get any missiles through and is forced to attack with beam weapons. This (hopefully) means they can be targeted by beam STOs (assuming the attacker doesn't have longer range tech). With enough of both the planet is safe, otherwise the planet is vulnerable to beams or missiles.
Another aspect is that fortification makes units harder to hit, the way I think about it is that heavily fortified units have many prepared positions they can move between (via underground tunnels or something) rather than sitting in one place and piling up bigger dirt mounds or concrete layers to protect them. The maximum fortification level is based on unit type and whether they have construction units helping.
This means that STOs can survive beam bombardment by virtue of being difficult to hit regardless of what is shooting at them.
Finally you can't distinguish STOs from other ground units until they fire, which gives the defender the possibility of deceiving the attacker into thinking there are no long range STOs until they are well inside firing range.
You can implement this by having abstract levels of point defence fortification. Each level represents a hardened network of mobile vehicles with point defence weapons and radars for detection, statistically some useful fraction of the network is in the correct position to shoot the incoming missiles. The system remains hidden until activated.
Each level of point defence fortification provides some suitable amount of point defence (maybe 10 shots?) and costs a suitable amount to build and maintain. There should probably be some limit on how high the level can get and where you can build them (like a minimum population and body size, it would be difficult to have a vast network on a small asteroid).
Hits from missiles and beam weapons can degrade the point defence fortification, reducing its ability to protect the planet, but those shots don't necessarily destroy the units, they might just block tunnels or destroy firing platforms. This can be abstracted as hit points, when all hit points are lost the fortification is considered destroyed, the output should diminish as the fortification takes damage.
(This is somewhat difficult to calibrate without a firm number of shots it can fire and hit points, I'm assuming 10 each)
The simplest option would be to reduce the number of shots by the number of lost hit points.
Alternatively you could have a 50% chance of reducing the number of shots by the number of lost hit points.
Alternatively you could roll 2D6-2 and if the damage is larger than the number rolled then the output is reduced by the amount of damage (this might just be my penchant for bell curve distributions talking).
I think you mentioned that planets are divided into 6 hexes so you might want to keep track of defences in each hex separately, which could increase the amount of book keeping during a battle.
You then have a choice of duplicating this system with beam weapons or putting beam weapons on PDCs. Arguably you have the same choice for missiles. While they are already established in universe to be stationed on PDCs, that could simply be a strategic holdover based on outdated philosophies rather than new operational realities. Or you could make it a HT9 system so that everyone has an excuse for not having it researched yet.
Interesting. I have long played around with the idea that if drive-fields didn't work in atmosphere combined with a gravity well, then that would change the equation. After all, if the missiles that every fleet is equipped with didn't work any more, then the threat of bombardment is negated without special equipment and surrender would no longer be automatic. I always get lost in trying to devise a combat system that is abstract enough to cover an entire planet, but yet still detailed enough to be interesting.
For now I've decided to continue pushing forward with the current hybrid system from the later Starfire products that I've been using.
Kurt