Aquila is a great first time casual player's weapon. I don't honestly know why they didn't use this weapon for the demo to reel in those people who want to feel of 60fps while using a weapon that does everything for you. Maybe they will include it in the second one in hopes of getting more pre-orders in.
Aquila looks amazing, it's like they dumped all their creativity on the angel weapons and made the demon weapons as boring as possible
I can see what you're getting at. :p I think it's heir nature sorta; like the demon weapons are heavy and everything has a lot of umph, but because of it everything is pretty direct and to the point as opposed to the flash the angel weapons convey with their aoe, speed, and aerial maneuvers.
Personally I was hoping they'd make the gauntles an angel weapon; they'd be a set of gauntlets and greaves that allow a wide variety of martial arts moves at insane speeds.