So...what exactly is the valkrie supposed to be?

Where did you get the 280 mph from?

175 mph sorry, 280 kph.

Eh... The Valkyrie's firepower and armor are both pretty mediocre. Its armor in particular is a joke. It could definitely use substantially more armor against flak and lock-ons.

Thats not all. Given the Role the Devs have intended you would need:

- more top speed and a passive AB (like Harasser) so you can move your Squad in fast
- complete imunity for players in the rumble seats against splash, so you can get them to the destination alive, without loosing them to AA
- a change from light to heavy armor so you cant be downed by every little Infantry guy, how are you supposed to drop troops if every single guy can shoot you down?
- better armor against AA and Lockons, the amount needed to shoot down this 6 player transport is just rediculous
- more power for the gun, you are supposed to drop troops and offer support to them, but if you drop your troops you have noone left in the rumble seats, so its only Pilot+Gunner
- a complete change of the model and animations to allow for free look from the rumble seats, its obvious that it wa sonly intended for 2 rumble seats as the ones in the back get tehre sight blocked by the wings

I could also think about a second set of weapons so the gunner can switch weapons.

Interesting mechanics that would give the valkyrie an edge in its either of its roles

For transportation:
Shielded rumble seats utility/defence slot. Gives all infantry Nanoweave and flak armor in accordance to its level (level 5 shielding gives level 5 nano and flak while in the seat)
Phantasm module, been mentioned before, essentially valkyrie cloaking
Smoke launchers. Fires two or 3 smoke grenades in a volley from a front mounted position on the valkyrie, giving disembarking troops (as well as itself) cover when it touches down
Shield projector: Instead of the forward mounted gun, the valkyrie's gunner now has the ability to project a shield that is about a 30-45 degree arc anywhere around the ship, the shield is impenetrable, but it trades of its offensive power for more survivability.

For CAS:
Point defense system that will down any rockets but may only hit one at a time (and so be overwhelmed by multiple lock ons)
Backburner, forward facing afterburner that can give the valk immediate thrust backwards (much more limited in fuel and time then normal forward burners)
Air mines, limited amount that can be resupplied. will not insta kill an esf but will explode after its in flak range.

Valkyrie is too big.

Like really, I could handle it being slow, tissue paper weak if it weren't so freaking huge.

It seems quite large to be based on the Littlebird. I guess real life scale is a lot different to BF3 hehe. Still the Valk seems a monster of a craft and the Littlebird is kinda tiny.

I guess the gunner spot and the 2nd bucket seats altered it a bit too much.