This is pretty cool! I'll probably adapt some of it if my group decides to do a future/space campaign rather than an urban fantasy campaign next. Unless we decide to use the new Alternity rules, if enough of the rule set is out. We really like Alternity.
About martial arts and primitive weapons in space.
One of the reasons MMA is so strongly a "ground and pound" game is that you can't try to break people's joints in an MMA match. (Call it a no rules fight all ya want, it's a fighting sport match. Period.) I always come back to anecdotes, when it comes to role playing games, not norms, because even in a fairly gritty RPG, IMO, PCs should be able to do semi-reliably what real humans only do in extraordinary circumstances.
The relevant example? The three times I've seen "traditional" martial arts




the norm of "grappling and larger size wins fights". The best example involves my friend who is female, 5'6", and used to compete in Kung Fu tournaments, and a 6'?" Douchebag who trained at my buddy's MMA focused gym. I don't want to post a text wall, so I'll skip to the end. She bruises from his grip, but she broke his left wrist and pinky finger, right knee, cracked at least 3 of his ribs, and gave him concussion from kicking him into a stone facade wall.
Not a normal circumstance, but certainly within the bounds of a fairly normal person. I mean, it's not like she was on supplements or anything, and he was tryin, she was just better, and more competent to break parts of a person.
So, imo, it makes sense to consider using mechanics to make martial arts a high risk/high reward proposition.
In my system, a few factors make melee combat viable.
*speed+close proximity makes it really hard, irl, to shoot someone. More than one special forces train extensively to avoid being disarmed and to shoot people effectively at very close range for this reason, while others train extiensively to be viscioualy Lethal when disarmed. So, shooting a charging enemy is hard. As is shooting he guy punching your buddy, without hitting your buddy.
*you can specialize in disarming and disabling, rather than just damage
*it is higher risk than shooting from cover. Absolutely. It can also end a fight more quickly, sometimes less lethally, and often accomplish other important goals that are time sensitive, where being bogged down with a shootout would be a bad call. Also, futuristic armor and medical science makes it less likely that you will actually die. Be injured and need to convalesce, sure, but death rates are lower.
*hobbyists and people in high security settlements, and in space environments where ballistic weapons are dangerous for everyone, have developed "primitive" weapons into very high tech versions. Telescoping batons, bladed weapons, combat gloves, etc, and lightweight armored space suits are much safer for fighting on a ship or station. Either the interior walls are hard enough to stop bullets, in which case they will ricochet, or they aren't, in which case...ya know...you're on a bloody space vessel.
So, no sane person specializes in bows but not in guns, for instance, but high tech bows can fold into a package the size of an 80's brick phone, and unfold into a "shortbow" sized bow that functions more or less like a compound bow. Arrows, meanwhile, can telescope into the size of a comically purportioned sporting dart, and telescope out quickly enough that it can be done as part of the action used to draw and shoot.
imo, people would absolutely do that. Like, 100% guarantee.
Anyway, just some thoughts on punching and stabbing in space.