Why Neji? Kyuubi also takes extra damage from elemental attacks, so ideally, you want to run ninjas with elemental standard attacks and mysteries. However, free ninjas for fire are quite limited so I would run Anko, Tenten, Guy. The fire main is going to be the main damage dealer, so having these ninjas to buff him is the most efficient tactic IMO.
This is the lineup that I run with: Scarlet Blaze Guide. WB Asuma will be obtainable later on from the shop (according to the post about ninjas in the Chinese shop). Otherwise, he can be replaced with Tenten. Iruka can be replaced with Guy or Pain Shurado.