Well in terms of the better fire moves it can learn you have your options of
- Fire Fang
- Fire Blast
You also can teach it Fire Charge, but that's more of a secondary move as it lacks power. I'd say that if you have a higher attack and really want to replace Flare Blitz, then I would go Fire Fang, which it learns as a Growlithe or via Move Remember' if already evolved.
If you have a high Special Attack then you have a few more options. Most powerful is Overheat. If you don't like the Special Attack drop after Overheat, then you can choose Fire Blast which is not quite as powerful, but quite good. If you don't like the accuracy of Fire Blast then your last option is Flamethrower, which has good accuracy and decent power.
I would say these are your best choices from Arcanine's movepool.