Tactical uses of the Swordwind host:

As mentioned above, a Swordwind host will be somewhat less flexible than a "normal" Eldar war host. Aspect Warriors in Epic are extremely assault-oriented and will not fare well in a firefight against any but the weakest opponents. Aspect Warriors are also relatively expensive troops, so while you can have a sizable Swordwind host, it will use up a lot of points.

Sample Offense-oriented Swordwind host:
HQ:
Farseer mounted in Falcon: 104 pts.

Main Force:
3 squads (6 total units) of Aspect Warriors mounted in 3 Wave Serpents, each squad upgraded with an Exarch: 147 pts.
2 squads (4 total units) of jump pack-equipped Aspect Warriors mounted in 2 Wave Serpents, each squad upgraded with an Exarch: 114 pts.

Support:
2 squads (2 total units) of Guardians mounted in 2 Falcons, each squad upgraded with a Warlock: 94 pts.
3 squads (3 total units) of Shining Spears, each squad upgraded with an Exarch: 60 pts.

Total Detachment cost: 519 pts.    Total Detachment Morale: 11 pts.

As you can see, this detachment is extremely expensive, over 1/3 the cost of a typical 1500 pt. tournament army. It's very dangerous in an assault, but could be easily beaten in a firefight and could be shot up equally easily by enemy anti-tank troops. You can buy a lot of Guardians for 500+ points, or a lot of Engines of Vaul for that matter, so in order to get the best effects from this sort of Swordwind host you have to be very careful with your forces. Use speed and cover (any Eldar detachment's good friends) to minimize casualties until you're ready to strike. Even though its assault value is very high, against some enemies, especially large Tyranid and Ork hordes, its odds of prevailing in an assault are not particularly good. Only in a large game (2500 pts and over) would I ever field this entire detachment. But the overall structure is valid for a scaled-down version suitable for smaller games.

Sample Defense-oriented Swordwind host:
HQ:
Farseer mounted in Falcon: 104 pts.

Main Force:
5 squads (10 total units) of heavy weapon-equipped Aspect Warriors, each squad upgraded with an Exarch: 205 pts.

Support:
3 batteries (6 total units) of Support Platforms: 120 pts.
2 squads (4 total units) of Wraithlords: 112 pts.

Total detachment cost: 541 pts.   Total detachment morale: 11 pts.

Again, this detachment is very expensive points-wise, but can pour out a lot of firepower within its 45cm range (30 firepower, 6 anti-tank shots). Again, I would never use this detachment except in a large game, and due to its overall lack of mobility, only in a scenario where I was tasked to defend an objective. This is the kind of detachment the Biel-Tan would hold off a rampaging Ork horde with. The Swordwind would certainly be able to hold its own in an assault far better than a Guardian-based force, which is essentially what you're paying the extra points for, but its low numbers in comparison could easily work against it. Its major weakness is the overall low armor value of Eldar troops, and could easily be bombarded by enemy artillery if adequate cover isn't available. Again, a scaled down version could be based upon this design for smaller games.

Sample Deep Strike-oriented Swordwind host:
HQ:
Farseer: 75 pts.

Main Force:
5 squads (10 total units) of Aspect Warriors, each squad upgraded with an Exarch: 105 pts

Support:
5 squads (5 total units) of Aspect Warriors: 50 pts.

Total detachment cost: 230 pts.     Total detachment morale: 5 pts.

This force is tailor-made to be deployed via Vampire Raiders. Four Vampires could transport this force anywhere on the battlefield, provided adequate air cover is given. It is decidedly offense-oriented, as most successful Swordwind hosts will be, and once deployed is quite limited in mobility and vulnerable to being shot up and bombarded with artillery. But if used at the right time, it could break the back of an enemy army.

Overall thoughts: The Swordwind Host accurately reflects the proportion of Aspect Warriors in a Biel-Tan craftworld force. It can be staggeringly powerful in an attack, and hold its own in defense, but can be very vulnerable due to its low armor value and small numbers (even for Eldar!) A smart enemy, when seeing the Wave Serpent-embarked Swordwind host listed first above, would try to blast the transports with anti-tank shots and pin down the surviving Aspect Warriors with artillery or tanks. The very high cost of Swordwind detachments means they will inevitably be quite small, increasing the danger of being reduced to half-strength and their large morale value being deducted from the army total. The Swordwind host adds more options for an Eldar player when designing his or her force, but even more than with normal Eldar armies, proper use of the Swordwind is required to get the necessary benefits from it!