Talonflame

Despite its status as what is basically "Generation 6 Pidgeot", Talonflame had an extremely interesting introduction in the main series. Its signature ability, Gale Wings, let it move before basically any other Pokemon with its Flying Type moves, and its use of Brave Bird made it absolutely feared in its debut generation.

But then Gale Wings was nerfed in the follow-up generation and Pokemon Go doesn't have abilities in the first place, so Talonflame can't hide from its status as Generation 6 Pidgeot any longer. It's basically worthless in the PvE metagame, and should only be gotten for the sake of a dex filler.

My how the mighty have fallen....

Best PvE Offensive Moveset

• Fire Spin is the strongest fast move, and recommended whenever it can be Super Effective.
• Incinerate* is a slight downgrade, but is still an okay choice considering its limited availability. 
• Peck falls behind in performance, but benefits from STAB, pairs with Talonflame's best Charged Move option, and is useful against Fighting-types.
• Steel Wing doesn't suit Talonflame. 
• Fly is the strongest charge move, and recommended whenever it can be Super Effective.
• Brave Bird is a step down.
• Hurricane definitely falls short.
• Fire Blast is a downgrade stat-wise, but can be useful against Steel and/or Ice Pokemon.
• Flame Charge is quite poor for offense, despite benefiting from STAB. 

Best PvE Defensive Moveset

• Incinerate* is the best for defense due to its significantly higher base power, plus STAB. 
• Fire Spin is the next best option, but has less than half the base power. 
• Peck gets STAB but doesn't offer anything special in terms of coverage. 
• Steel Wing is useful against Talonflame's weakness to Rock-types, but is resisted by Electric and/or Water Pokemon. 
• Flame Charge can be used frequently as a 3-bar move, but is painfully slow and easy to dodge.
• Brave Bird has a relatively early damage window, and is the hardest to dodge. 
• Hurricane is strictly inferior, but not too far behind.
• Fire Blast and Fly are the slowest options, making them the worst options for defense. 

Incinerate has an edge over Fire Spin due to superior energy generation, but can be more difficult to use in practice due to its very long animation. Peck and Steel Wing both offer similar damage output and below average energy generation, making them less desirable. 

Flame Charge offers a guaranteed buff to ATK and has a moderate cost, allowing Talonflame to set up and sweep. Fly is Talonflame's cheapest Charged Attack and generally the preferred Flying-type attack over Brave Bird due to its reliability, but running both of moves can be a viable strategy because their combined costs fit perfectly into Incinerate's energy. Brave Bird is a very efficient and powerful move that deals significant damage, but can be risky to use due to its self-debuff. Hurricane and Fire Blast demand too much energy to use.