Thanks Ninja, unfortunately Alistair is completely blind. I decided it wasn’t worth replacing the video card since he’s 5 years old now and has a plethora of other problems…so I broke down and ordered a new laptop. 
Tarek, Agargara is actually Sumerian for fish. (Or it can also mean sheep droppings, apparently.) It doesn’t have anything to do with my nationality though, I’m from the US. (I did live in Japan for a few years as a kid though.)
Anyway, here’s my take on Legend of the Gunstars:
It’s D major, but borrows the lowered sixth and seventh degree from D minor. (Hence the “minoresque but not” feel as you say.) The whole step motion between all these B flat and C major chords contributes to its “epic” sound. It also sometimes uses a minor subdominant (g minor), also borrowed from D minor. While there are some 1-4-5 suspended chords, there aren’t any traditional dominant chords. Instead of a normal dominant (A major) you get the lowered seventh degree (C major) acting as a sort of dominant. From my experience, this is pretty common in movie and game music that’s meant to sound epic.
In the first part, there’s a pedal point on D (as the harmonies change above, there’s always a D in the bass.) After the pedal point section, a little less than a minute in, there’s a brief interesting bridge kind of thing. It starts off with the same chords we’ve been hearing before, but he raises and lowers the sixth degree for a little switch up, throwing in in a a minor vi chord. The resulting bridge chord progression is something like this: I - iv - VI - VII - vi - iv - VI - VII
The rest of it is the same as the first part with the pedal point on D and lots of VI and VII chords. The final climax has some nice chromatic movement, with major triads starting with F major going down by half steps back to D major.
Empire - The Final Assault has the same deal going on. It’s D flat major, but once again borrows a lowered sixth and seventh degree from the parallel minor, hence all the A major and B major chords. The lowered seventh degree once again acts as dominant. I won’t go into detailed analysis unless you want me to – almost all of the track is I - VI - VII, like Legend of the Gunstars.
I’m not saying these are the only possible interpretations, by the way – theoretical analysis is somewhat subjective.