[Swifthawk Agents - Not all competitive lists are from new releases]

I think the most effective Swifthawk list you could run at 2000 would be as follows:

Allegiance: Order

Leaders
High Warden (220)
Skywarden (160)
- Zephyr Trident
Skywarden (160)
- Zephyr Trident
Archmage (120) (General)

Battleline
20 x Reavers (640)
5 x Reavers (160)
5 x Reavers (160)
10 x Spireguard (120)
- Swifthawk Agents Battleline
10 x Swordmasters (200)
- Eldritch Council Battleline

Battalions
Guardians of the Dawnspire (40)

Total: 1980/2000

You would run a fast mounted ranged deathstar consisting of the 20 reaver unit, the two skywardens, mounted archmage and use all the foot troops and the high warden to attack enemy shooting and delay enemy charges. This unit can theoretically put out 120 shots per turn at 4's to hit and 2's to wound resulting in an average of 50 wounds caused per turn in shooting. With the mage bubble and inspiring presence it won't die incredibly easy. Where it falls apart is, if they make their saves, or just hunker down in cover by an objective, you're just going to be standing at length shooting while they win the game just sitting there not dying fast enough. 

[Swifthawk Agents - Not all competitive lists are from new releases]

On those lists, why would you split the reavers evenly? Seems like you should put 15 in one, 5 in the other. That way you can get 45 shots with the battalion ability instead of 30. Seems it would be better to split the spireguard for battleline.