Bruiser Dragonfire Adept?

[grae]

Is there a way to do this? Is there a way to do this that's playable from level 4?

In the handbook, I read a mention of a biting build that involved Totemist, Barbarian, Totem Rager...?

If impossible, what would be the toughest DFA you could make (again, starting from level 4), in terms of survivability and being physically focused? Obviously, focusing on breath weapons over invocations.

[Twilightwyrm]

One level of DFA gives you a breath weapon, which gives you access to the Furious Exhalation feat. This gives you a 2d6 fire (or whatever your breath weapon element is) damage to any bite attack you make. I'm not sure if Totemist can give you extra bites, but it would help a bit for a natural attack build. One of the best of those is the Totem Rager (another being druid).