That'd be crazy Broken, Talonflame is already crazy as is with Priority Brave Bird, and a max attack of 287. 165 Base Attack gives a max attack of 471 (64% more damage). Couple that with Priority? That's just insane.
Oh just throw something in that resists flying? Like Tyranitar or Heatran? Well about that. Honchkrow learns STAB dark moves like... SUCKER PUNCH. Oh also SUPERPOWER. Not to mention you can also get it an attack boost before Mega Evolving with Moxie.
This would break things and be banned, I'm almost positive.
That... oh goodness, that won't ever die unless you have grass coverage. Regenerator, Recover? Give it Scald, Recover, Ice Beam, Toxic. This thing is mean.
Love the premise though.