max out one of the DA units. drop the other one. put the fraggons in the other wave serpent - they need to get close to get a kill . sensible opponents wont come anywhere near them apart from with assault infantry ! [tau will just stand off and pepper them]
stick one lock on a bike and then you have some anti-tank in the bike squad as well [two spears]
base level locks with spears are also good anti tank and can jump in the empty wave serpent once your dragons have performed hari-kari - i sometimes run even a small unit [2-3-4] as useful anti-tank back up; they also boost your warp charge dice for the farseer if he gets decent powers
i generally dont bother with a chin gun on a falcon since it wants to stay at range - but you could always hide your locks in there [or even 6 DA] - i wouldnt use falcons for dragons as they need to get really close these days with all the A14 around.
riptides hate dragons so keep them as a threat and he will be wary
wraithlords are lovely models but are on the weak side of the survivability index . he will spend most of the game hiding !
Afraid I have to disagree with some of that. Wave Serpents are arguably better at keeping their distance than falcons thanks to the serpent shield. Serpents are also often seen as bigger threats than falcons meaning they'll probably draw more fire. That said, serpents with scatter lasers put out enough twin-linked shots that you can jink the serpent without giving up as much offense.
Sticking a lock on a bike with a spear pairs well with a farseer on bike with a spear, agreed. Just don't forget that bikes can be reasonably scary by simply shooting shuriken cannons at a range, so don't risk getting close to the enemy before you have to!
A trio of 'locks with spears isn't terrible anti-tank, but it's definitely not one of our more effective options for the points. More dragons give you more durability and fire power for fewer points. I'm also guessing the OP bought the farseer+three warlock kit which means he only has one spear. 'Locks *do* boost your warp charge pool though, which is nice. Also, dragons aren't as much of a suicide unit as they used to be. Between battle focus and their improved armor save, they actually have a pretty good chance of surviving the following turn if supported well.
If you do take a wraith lord, don't work too hard to hide him. The lord will, unfortunately, die pretty easily, but he'll also scare your opponent big time! The nice thing about 'lords is that, unless you ropponent brought the right guns for teh job, they can actually soak up a fair bit of fire power, and they *do* hit hard if they make it across the board. Try to keep a wraith lord cheap if you take it, and think of him as a bullet magnet.