I have played for a long time and I have noticed that statistically, crew that work in a defensive buildings are the same as the people who work in an airship. If you think about it that is wrong because no self-respecting general or government would just put any cabin boy in defense of a major city.
In an airship it makes sense; all that crew members have to do most of the time is shovel coal, so to have special armed guards or marines that defend a ship works. But historically normal people wouldn't defend a city (not counting angry people with pitchforks), it would be trained infantry men who knew more then just how to aim and fire a cannon. I think the solution to this is to not just strap a rifle to every crew member in a building, but to have a new module called an Armory that stores guns and ammo for the use of the crew. When a building is being boarded the crew will try to rush to the Armory and try to arm themselves.
Special guards who are always armed or elite marines are good but relatively constraining ways of defending a building, but, if given enough time, to have every crew member have a gun makes sense. Air marines will always have the upper hand because they are specially trained but i think this is a good way to balance out boarding, so that 6 marines don't take over a huge fortress.
And when Zark adds land base battles with troops running around we can perhaps have artillery.
So I don't really like your idea because it makes things more complicated. Instead of just defending, units have to go to an armory first, and also balance that with all of their other duties.
Currently, everyone is actually armed. Normal crew have pistols, and some chance of defending themselves. (I should really add a coat of arms bonus that makes this more powerful, come to think of it.)
And you've got guard barracks exactly so you can put in defenders.
Land battles: This is one of the things I want to achieve in version 7. I'm not quite sure about the balance details yet, but hopefully it will work.
Maybe the sailors on buildings could be replaced by soldiers, who are better at close combat that sailors, but not at good as Marines.
Zark I actually never really noticed that the crew members had pistols I guess I never really looked closely at the crew. Never mind about my idea then… your way is much much better.
yeah slimy that is what I wanted at first but I figured there might have been a balancing issue which is why i suggested them having to run to a separate room.