Ok i play against most armies with this list and have had a lot of success losing just 1 in my last 10 games. And that was mainly down to a IG L russ that would not die.

HQ: 'el fireknife with shield drone and 2 fireknife bodyguards.

HQ: 'el with AFP + MP + TA + HWTL + HWMT + shield drone

Elite: 3 torch squad (single HQ attached to this hense the shield drone and HWTL)

Elite: 3 fireknifes (leader having a shield drone and TA+HWMT)

Troops: 6 firewarriors (use pathfinders devilfish)

Troops: 10 kroot with 2 hounds

Troops: 10 kroot with 7 hounds

FA: 5 pathfinders with DF (SMS + DP + FD)

HS: Hammerhead ( burst cannons + DP + FD)

HS: 2 broadsides with ASS ( leader has shield drone + HWMT and HWTL)

Now as a said i dont plan on changing this all comers list but we have talked about playing some 2 K games (which i have said i would use SM but i want to have a tau list just in case)

Anyway the extra 500 points, i was thinking:
another 5 man pathfinder squad with DF
a piranha with fus blaster + DP + FD.
another broadside in his own HS slot but with TA instead of ASS.
That makes 335 points by my count so i have 165 points left.
So what to add?
a 4th broadside? + a 6 man FW squad to go in the pathfinder DF?
a 4th Broadside + ?????
a 2 man battlesuit FK squad???
another 6 man FW squad and a second piranha????

what you think i should do with the 500 points??