ok so my 2 main openants one hu has tau (I can pretty much beat him any time(4-1)) and the other is an eldar player hu has 1000pts at the mo

he has: 1 autarch on jet bike
1 warlock on jetbike

2x 5 man jetbike squads

2X vypers

and 2X grav prisims

now i played him and the tau together vs me and i pretty much ignored him took out the tau then hunted down his regiments, but what would be the best troops to take vs him, (I still have 4th edition codex but will get 5th ed during weekend) from my selection i have:

1 chaplain-on bike
1 chaplain
1 librarian-on bike
1 librarian
3 captains

then- 2 veteran squads 1 cc and 1 with bolters
1 cc termie squad
2 nrm termie squad
1 honour gaurd squad
1 dreadnought

then- 3 10 man tactical squads
2 7 man scout squads
2 razorbacks
2 5 man bike squads

then- 10 man assault squad

and finally- 2 whirlwinds
1 landraider (crusader or nrmal)
1 predator
3 5 man devastator squads
and then a custom tank which is basically a vindicator with an assault cannon

so ideas please