I agree with MarksmanCypher:
- more dire avengers. 5 of them (even using firestorm) arent going to do much. I like the weapon options on the serpent though: you can use it to support the avengers after they disemark.
- Eldar missile launchers are great against tau!
- i'd give the warwalker double weapons to take best advantage of the non-twin[linked rule. shuriken cannon/missile launcher isnt a bad choice come to think of it, but id stick with missile launchers or bright lances to get some more AntiTank. maybe 1 missile launcher and 1 bright lance?