First off, an apology- I had a look around for somewhere suitable to put this and putting it in the NetEA development forum seemed like the wrong place, as it's just a quick conglomeration of ideas.
Anyways, I was thinking about a list which includes some of the Tau units which don't feature in any lists, particularly Breacher Teams, XV9 and Ghostkeel and threw together this list. I understand the reluctance to make normal Tau FF kings, but the Breacher Teams and XV9 are fluffed to be basically that, hence the direction of this list.
Not sure about the Sa'Cea sept, but its the next biggest Fire Warrior world so it made sense after Vior'la. Fluffing it as a cityfighting force made sense to me- I stripped out a lot of the long ranged AT guns (Railheads, Broadsides) in exchange for FF aptitude and short ranged macro (although the Fusion Collider on the Ghostkeel is pretty silly I readily admit). The Stormsurge and Supremacy Armour are taken directly from the Vior'la list, as those are Tau siege pieces, as much as the Tau have a concept of sieges!
It also includes some other Tau variants which have been around for a while in 40k- Sniper Drones, Missile Broadsides, XV25 with Fusion Blasters and some of the FW XV8 variants.
Comments and criticisms welcome and encouraged, it may be absolute nonsense for all I know!
Edit- Already got a bunch of thoughts of my own about what to change-
• One Breacher Cadre as a compulsory Core Formation (to accompany the below change)
• Kroot as a Core Formation (Kroot are very common in Tau urban warfare)
• Gun Drones upgrade 2 units for 25 or 4 for 50 (mostly fluffy as I reckon Gun Drones would be very useful in urban combat)
• Gun Drones as a formation- 8 units for 150 (for the same reasons as above, and Gun Drone squads have always been a thing in 40k. They also provide a cheaper formation option)
• Ghostkeel gain teleport (in keeping with their stealthy nature)
• Ghostkeel lose Deflector Shield but always count as being in cover (ditto)
• Ghostkeel formation size 2-3 not 3-4 (mostly to balance if they do get teleport)
• Ghostkeel always bonded (fluffy)
• Revise XV9 FF- remove EA or MW (a friend has already commented that XV9's "look like Terminators on speed")