4. Interior fights are often not limited in weapon choices, big guns and explosives are used. No one's worried about holes after the ship-to-ship fight. IMTU only in a few areas will hits by heavy personal weapons cripple the ship or worse. So boarders typically burn through internal hull to the command center and engineering. The primary goal on military boarding is to disable self destruct capability, by (1) frying/hacking the comp and any other remote means, (2) physically securing and disabling manual means, (3) securing the engine room to prevent drive oveload.
----------------I don't necessarily agree here, but its YTU in this case. IMHO or better said IMTU all this will depend on how desperate the crew and boarders are, how delicate the cargo (if present) is, and I certainly think that pirates are going to try to minimize damage to the ship - if possible. They want that ship. Its worth a lot. Sure, you can patch a hull pretty quick. I am sure that they have something for that, but the bridge is going to have a lot of sensitive instruments and such that you won't want to destroy - once again IF POSSIBLE. If Pirates are boarding a merchant I think that they will:
a) Try to have as much beforehand knowledge about the ship, its cargo, its armaments etc. before attempting to take it.
b) Most probably will have some people of their own on board if possible (this also facilitates 'a' above).
c)Will try not to use weapons that damage the ship too much.
d) Will try to negotiate a surrender with the crew if possible.
e) Will try to drag the ship away and besiege it before attempting a costly boarding action if they are unable to negotiate a deal or take the ship by deceit.
5. IMTU life is cheap to most polities and the warrior culture high so taking military boarders hostage after you surrender, really not much good is to come of it. Marines are prepared to die in boarding fights and for the cause. If the cause means your own blow the ship up so it can't escape, so be it.
-------------With the feudal system being in place there is an agrument to be made for pirates taking experienced crews and demanding ransoms. IMTU Life is not quite as cheap as in yours. Sure, if the marines board a pirate they are probably going to kill a lot of them, but they will try to take a few prisoners to learn more about the pirate clan's operations. I agree with you though that the Imperial Navy and Marines are probably pretty hard on pirates.
6. With respect to pirate boarding, IMTU there are certain understandings and codes of conduct about it, especially since much piracy is privateering. You can agree to cease ship fire and agree to be boarded but can still fight back. If things are going badly you can still surrender and expect to not be slaughtered, IF you turn over the ship codes. Likewise, if a pirate surrenders you are expected to accept it, but you can fairly ransom him back to his comrades. The only enforcement is reputation and if word gets out you didn't follow the code then prizes will fight to the death and you may find your letter of marque revoked.
----------------------Yeah, I agree with you here. I could even see that there might be some formalized boarding "rules". Maybe even some duels to resolve certain situations. Of course, I wouldn't expect the pirates to keep their word. Still, there might be some "honorable" pirates or privateers out there.
-----------------I don't know about ransoming pirates back to their comrades. I suppose it would depend on the gang. Some of them might be like the mafia and try to kill captured comrades so that they have no chance of squealing. I could see the Imperial Navy arranging hostage and prisoner exchanges. "We'll give you your captain 'black-jack' back if you release the crew of the Artemis." Yet, in most cases I bet the Imperium has a hard policy toward pirates and those marines boarding a pirate ship are not going to hold back when it comes to the weapons that they use . . . unless of course the pirates are holding hostages.
--------------------In short, I guess IMTU it all depends on the situation.