Rock, Paper, Scissors: Weapon and Damage Mechanics, Sample Weapons, Armour Progression, and remarks on AI
“Hokey religions and ancient weapons are no match for a good blaster at your side, kid.”
-Han Solo, Star Wars
"With my trusty Monteba? Any time."
-Togusa, Ghost in the Shell
"An elegant weapon, for a more... civilised age."
-Obi-wan Kenobi, Star Wars
"Well they tell you: never hit a man with a closed fist. But it is, on occasion, hilarious."
-Mal Reynolds, Firefly
"The shield turns the fast blow, admits the slow kindjal!"
-Dune
"Your superior intellects are no match for our puny weapons!"
-Kang and Kodos, the Simpsons
Ah, where would SF be without lasguns, photon torpedoes and power armour? ...Arrakis, probably. But anyway:
Shields trump Ranged and Energy Weapons
Ranged and Energy Weapons trump Armour
Armour trumps Physical and Melee Weapons
Physical and Melee Weapons trump Shields
In addition, characters can try to Dodge or Parry attacks- which might require actual animations to that effect. If a character tries to dodge an Area-of-Effect attack, s/he has to physically move outside the AoE- which might be impossible without jumping, rolling, ducking, etc.
There are various obvious provisos you could add here: Shields and energy weapons consume power, parrying needs a melee weapon, physical weapons can't parry energy weapons, dodge attempts are encumbered by armour, ranged attacks need line of sight and are very hard to parry, energy weapons can have types: plasma, sonic, phase, electric, etc. etc.
I don't imagine the majority of classes are limited to the use of one particular weapon/armour combination. The real catch is here is designing an AI that can take the differences between various forms of weapons, items and armour into account. I covered this subject under 'window shopping' in the Generic AI thread, but in summary, you have to allow heroes to acquire 'virtual copies' of various items and abilities, which let them test out their hypothetical effects in the field before committing to a purchase. (Evaluating the hypothetical effects of an action before actually using would be enormously helpful to AI in general.)
And please, for the love of Gods, do let's have a sequel where characters with ranged weapons use hit and run attacks, or at least don't stand there like dumb schmucks while melee characters make mince of them.
Armour Types: Partial Armour, Body Armour, Power Armour, Myrmidone Armour. Several of these could be combined, provided they're not adjacent on the scale- (e.g, partial armour combines with power armour or myrmidone armour, but not body armour.)
*- Any of these could be combined with Shields.
*- Power Armour augments strength but lowers dexterity. Myrmidone armour, more so.
*- The actual quality of armour (and weapons) depends on the skill of the Artificer who creates them.
Sample Weapons or Abilities:
*- Plas-sabre: Precise light melee energy (plasma) weapon. Yes, it's a lightsabre ripoff, (but actually makes sense here.)
*- Konoch: Heavy melee physical weapon. (Klingon Bat'leth, say hello.)
*- Sonic Projector: AoE (cone) energy (sonic) weapon
*- Wooden Spear: Precise light physical (melee or ranged) weapon
Precise weapons take better advantage of dexterity, while heavy weapons have minimum strength requirements. Finally, these might represent some of the sample abilities available to, say, the Xenopath-
*- Arc Lightning: Heavy melee energy (electric) attack
*- Disintegrate: Heavy ranged phase attack
*- Shockwave: Heavy AoE (burst) physical attack
Part Cyborgs, Full Cyborgs and Artilects
These are potentially quite interesting, since Androids and- depending on how far cyberisation has progressed- Cyborg characters might have to be repaired rather than actually healing, and their weaponry or armour might be built-in (giving a boost in skill/efficiency,) rather than equipped. Then again, the Keepers of the Secret Fire and nanotech in general might help redress that imbalance.
Weapons of Mass Destruction
"The use of atomics on human beings shall be cause for planetary obliteration."
-The Great Convention, Dune
"You maniacs! You blew it up! God damn you. God damn you all to hell!"
-Planet of the Apes
Atomics, bioweapons, nanophages, antimatter conversion, artificial black holes- there are any number of ways to reduce a planet, it's inhabitants, or selected portions thereof to their constituent stardust and mop up aterwards. The problem is that ALL of these things are gigantically illegal. If you try to pull a stunt like this without gathering massive political and social support (by fair means or foul,) you will most likely prompt immediate and terrible military retribution from other star systems- every other noble house or faction will put aside their differences and pound on you instead.
Recovery and Injury
"I can't believe I'm saying this... but that was really exciting! I've never felt so alive! -What else can we slay!?"
-'Leegola', Futurama
"It's a rock! It doesn't have any vulnerable spots!"
-Galaxy Quest
*- Healing is harder to model plausibly in an SF environment, since there's no magic.
*- So... why not change the mechanics of injury? When a character reaches 0 HP, they... just fall unconscious.
*- Injured or unconscious characters lose health gradually, until they receive medical attention.
*- Characters die if attacked when unconscious (or reach a certain threshold of negative health.) However, enemies ignore unconscious targets while there are other, active, enemies around.
*- Health paks and actual healing skills can only restore up to 1/2 (or 2/3, or maybe 3/4) of a character's health, and these can only be applied outside of combat. Remaining health has to regenerate naturally.
...So, if even one member of a party is standing at the end of a battle, he or she can get the others on their feet, administer health paks, or otherwise make sure they get medical attention. (This assumes, of course, that heroes habitually travel in parties WITHOUT the player needing to intervene.)
Life, Death, and everything in between
"Removal of all limitations means removal of all points of reference. In the landscape of wild possibilities you cannot orient yourself and say, 'I am myself because I am here.'"
-Dune
"The world with nothing. The world with nobody."
"The world of freedom."
"Freedom?"
"The world of freedom that would never be constrained by anybody."
"Is this freedom?"
"Yes. The world of freedom. As a result, there's nothing."
-Neon Genesis Evangelion
Cloning can be used to 'resurrect' a character physically, but the problem is restoring memories. If brain tissue can be recovered then, sure, it's possible that most of a character's skills and knowledge could be restored, but maybe characters could also 'backup' their memories to a central database (the Collective and Initiates might provide the service,) or maybe a certain degree of 'XP loss' would be in order, or maybe the Gaia Effect or Monoliths could obligingly reconstruct individual personalities.
The use of these technologies- Cloning and Memory Backups- raise other questions though. For starters, legality aside, what's to stop you from cloning entire armies of a given individual? Or, what's to stop you from transferring one character's memories into another character's body, even an Android or Oracle? Would clones need to be the same age? Could you have a Cylon-style cycle of pereptual resurrection into new bodies, never ageing, never dying?
Heck, why stop there- add in the skills of genetic manipulation and nanotech, and it's possible to turn just about anyone into just about anything- and vice versa. You could theoretically turn a krech into a blade-runner-style replicant, or a human into a spacer, or a logician into an archon.
The point I'm trying to make here is that the limitations on the use of science in the setting are mainly social and political, not technical. Everything has been invented already. Stepping outside the box like this isn't a technological problem, it's a legal problem- rather similar to the use of WoMD, for similar reasons, and with similar repercussions. (Yes, even the Shapers/KotSF do have certain ethical standards.)