I'm modeling the turrets right now. So, should this ship have anti-fighter turrets, or just anti cap turrets? The Wookieepedia says it only has a few double turbolasers turrets. Keep in mind that older ships in Star Wars seem to forgo antifighter weapons, or have very few. It feels right that the marauder would do the same.
On another topic, I've decided to keep the long guns on the wings. I tried swapping them out, and it didn't feel right. So perhaps they could just be regular weapons in oversized turrets, or a big damage gun with a long reload (to keep its damage-per-second in line with other, smaller guns). The diameter of the barrel is big enough that it could be used as a missile launcher, if so desired.
I also didn't include a fighterbay in this model.