EDITORS NOTE - This is verbatim (but formatted slightly better) text from my forever delayed Complete Guide To The Eldar. While this, along with 99% of what I've typed, was done before the Nid Codex came out, nothing has changed to make Hawks better. If anything, having more Jumper Marines about just makes them 10x worse, because they can't escape...
Haywire Grenades, to allow some serious anti-tankery. Plasma Grenades, to allow you to assault even Troops in cover, after softening them up with the mighty Lasblaster. Or rather, Hawk Wings, in order to let you try desperately to stay in the 19-24” range of ALL enemy models with Rapid Fire weapons, while you pump that awesome S3 into them at a distance, advancing ONLY when you see a convenient enemy vehicle that is both empty, and doesn’t have a WS.
Hawks can either be run as an inadequate suicide unit, barrelling headlong into a vehicle, having a miniscule chance of destroying it, if stationary (if it moved, no chance at all) with no Exarch, to conserve points, or they can be used as a Bomb run every turn, which would work if they were a Troops choice. To do the latter, they need an Exarch. Jut so we’re clear, Haywire Grenades are cack, and only ANY use against things the Hawks otherwise couldn’t touch…I.e., everything - but that just makes them better, not good.
Power Weapon = Unlike with the Spiders, the Hawks aren’t in any way likely to survive in CC, and this doesn’t confer an extra A. SuperFail. Hawk’s Talon = Oh wow, someone upgraded the Lasblaster to a reasonable weapon! Unfortunately, the shots put out by this don’t give you any real advantage, as the puny Lasblasters will still struggle to wound anything tougher than a Ratling. Being able to force an extra 2/3 armour saves a turn Shooting is great conceptually, but if you’re using Skyleap, you can’t fire this, so it’s just not worth it.
Sunrifle = I see you’ve played Knifey-Spoony before! This has a greater RoF than any other gun you can mention. It’s S3, so it’s interminably weak, but having enough shots to expect an Exarch to miss is phenomenal. If you want the unit to shoot the weak-ass things they can expect to actually kill (i.e., GEQs) then this is the gun of choice. However, if there’s one thing the Eldar army doesn’t need, it’s extra a-I firepower…at S3.
Skyleap = The prodigious yo-yo ability. This is the reason many people advocate usage of Swooping Hawks, because they think paying 142 points for a single S4 Large Blast every turn is sensible. Well, every turn, except turn one. And any turn you don’t make their Reserve roll…So, potentially, once a game. Yes, the Grenade Pack is cool, and useful for thinning hordes, since it’ll probably kill more than 20 Lasblaster shots. Yes, Deep Striking onto an objective and blasting the enemy of it is cool, and potentially game-winning. Is it worth the points for the chance you won’t scatter, mishap and die, having failed miserably in your aim, and subsequently lose the game because you relied on a wholly unreliable tactic? No.
Intercept = Improves the unit’s ability to go Tank-Hunting from ‘negligible’ to, ‘slightly better than negligible’. Perhaps if they could attack more than once each with Haywires. Probably not even then. Putting this on an Exarch, and an Exarch in a squad being used for this role at all, is foolhardy at best, mentally deficient asshattery at worst. It’s irrelevant that it’s so cheap, because Hawks couldn’t kill a stationary Ork Trukk without using Grenade Packs or a Hawk’s Talon.
Just as further evidence, if it’s not apparent by now why Haywire are fail, assume 6 Hawks. Hitting on 4+ against a fast moving AV10 rear thing. A Spirit Stones’d Fire Prism, why not. 6 Attacks, so 3 hits. Each hit has a 1/6 chance of getting a pen, so 0.5 pens between 6 guys. You need 12 - more than the unit max, to average a pen on a moving target. So, .5 Pens., .5 fails, 2 glances. Glances have a 66% chance of doing nothing but preventing shooting. Awesome, it’ll move Flat Out away. Or Tank Shock, and send you running. Unless it just moved Flat Out, it can’t be destroyed by a Glance…it’s just crap. Don’t ever consider these adequate anti-tank.