my pokemon on emerald

[jay1996]

Marshtomp
Aron
Kirlia
Swablu
Machop
Manectic
I really want a fire like ninetails what should I add or take out to make it better? I plan on replacing swablu with rayqueza.

[Gamefreak]

Moved to in-game team rate. Please read the rules, as this does not belong in crmt.

[Mystical Jackal]

Marshtomp - Keep it. This guy is good.
Aron - No, throw it away. I can't bear having 4x weak too fighting and ground in the meantime. Replace it by the fire type you want. Ninetales is a good suggestion.
Kirlia - Nice special sweeper.
Swablu - Replace it with Salamence or Rayquaza (as you wish).
Machop - If you can evolve it into Machamp, keep it.
Manectic - I don't like it very much, but Manectric can learn Flamethrower and substitue a fire type.

[Sceptile Leaf Blade]

I generally prefer Lanturn over Manectric as an electric type. Lanturn has a neat immunity to electric and it can also act as a water type, which is handy with all the water HM's. Manectric doesn't get fire moves yet in 3rd gen, only in 4th gen.

Aron is actually quite good once it reaches Aggron stage. Although it has its flaws, its type combination combined with that insane defence stat gives it for all practical purposes immunities to normal, flying, and poison, and extreme resistances to ghost, bug, and rock moves. Keep it out of the way for water, ground, and fighting moves and Aggron does fine.