YES. Goku has recieved loads and loads of power-ups after he met bulma.
But before he met Bulma, he didn't get them and as such, wasn't relying on them. Keyword: AFTER.
Talonflames feats
Tanked a Fire Blast from its FE form as a Fletchling, Hit a Mega Lucario as a Fletchinder, Tanked a Fire Blast from a Moltres as a Fletchinder. Hit a Moltres as a Talonflame. Fought a Zapdos. Took down a mon in all its gym matches before going down, except against Grant. Took down a mon in all its league matches before going down, carried Ash through the matches with Valerie and Olympia (Literally against Olympia, since Ash and Frogadier would have been boned without Talonflame).
Base Greninja's feats. Umm... i can't remember any of them, except against Ramos and against an already weakened Bisharp, who fought Hawlucha and Goodra beforehand.
Greninja with power-buff: defeats Sawyers Mega, defeats Wulfrics Mega and assumely the match against that Altaria during the league (Which i don't count, since it happened off-screen).
So comparing all those feats: Talonflame is hands down the stronger battler of the 2 in base form and due to its feats, also the ace of the Kalos team, since it contributed more than the other members of the Kalos team (COMBINED no less).
You can't argue against facts, especially if they are handed to you on a silver platter.