Actually, he had 3 fire starter aces (Charizard, Infernape and Pignite). I count Pignite, because Krookodile came to late to count as the ace.
Krookodile's still the strongest thus he's the ace.
Pignite just got lucky and got the better treatment of the Unova starters.... and Ash's original Unova squad in general, like Bayleef back in Johto. This is really the first saga where you could actually say all that starters have been handled terribly, regardless of evolutions. But people are unfairly biased against Fire types for some reason and will claim Incineroar's equal to Charizard and Infernape when really.... he's not, he's light years away! He didn't get to do any big battles, the only thing he's got going for him is League wins and that's assuming they don't make the League revolve around Pikachu and Lycanroc like the Kalos League and Pikachu/Greninja. I mean it's already starting to look like way with how only Lycanroc can battle Gladion and how both hogged trials.... >.>
I'd say Incineroar = Torterra if anything, both started out great but as the series progressed....
I can get the claims that Rowlet is equal to Bulbasaur though, but I still don't agree. That's like comparing Oshawott to Buizel and Squirtle.
And I'm definitely not biased in favor of Fire types, Fire ain't my favorite type at all. Dragon/Dark are. Whenever people ask what Pokemon you wanna see evolve I pitch Totodile, Snivy, Oshawott, and Gible as they deserve it. Pignite and Quilava don't need evolutions, not because "Ash has too many fully evolved Fire types" but because they haven't done much to warrant another one.
And one final thing the "Ash has too many fully evolved Fire types" card people like to pull is also just as old as the "Grass starter never evolves" card the writers pull. I loved it with Bulbasaur and Snivy(Though I do think she deserves an evolution) but with Chespin and Rowlet it just got old. At least Rowlet has a legitimate reason for it unlike every other starter save for Piplup and Bulbasaur. You'd think the writers just gave up after Torterra lol I wanted Decidueye from the start, Incineroar too. Ash having two fully evolved starters in the same region
can work if done correctly, Torterra mostly failed because speed is Ash's greatest asset and it seemed the writers didn't know how to transit from a fast Pokemon to a slow tank Pokemon. I'm actually hoping gen 8 can give us that again, it'd be lovely to see.... especially if one's the Water starter. I'd just love to see a fully evolved Water starter, or an evolved one in general back at Oak's....