hey bro sorry for the delay, yes it does have a swivel cannon mounted underneath, i totally need to do another render of this, need to show the underside as well. just has a single mount. although a lack of swivel weapons does not prevent it from being a gunship. look at the mi-24 variant with a fixed nose weapon.
the AC-130 is a gunship and thats like 5 times the size of this thing, in reality this isnt much larger than today's largest gunship (think its the Rooivalk)
gunships also dont necessarily need armour. its all about a balance between durability and maneuverability. few gunships today actually have armour since AA weapons will tear them apart anyway if they hit. so its better to avoid incoming fire, that being said, the reaver has light armour
I was commenting on the guns, they looked as if they could traverse up or down, so I was commenting if they could. True with regards to real life, but this thing is Sci-Fi, may not have enough armor to withstand whatever it's up against, but the design itself looks to be pretty durable.