You're forgetting Car Carrier and Tank. Admittedly Kyoryuger and Gobuster probably aren't the best example for what I'm talking about. Gokaiger and Goseiger however are as they introduce the exact same amount of auxiliary mechs in the exact same span of episodes as Ninninger.And the difference here is that Paonmaru and UFOmaru are auxillary mecha! Stegotchi, Dricera, Parasagun, Zakutor, GT-02, RH-03 are all assigned to rangers! the closest you get is Shield Ressha in episode 4.
You're forgetting Car Carrier and Tank. Admittedly Kyoryuger and Gobuster probably aren't the best example for what I'm talking about. Gokaiger and Goseiger however are as they introduce the exact same amount of auxiliary mechs in the exact same span of episodes as Ninninger.HTML:
Gokaiger: Episode 1:Gokaioh
Episode 3:MagiDragon
Episode 5: PatStriker
Goseiger: Episode 1:Gosei Great
Episodd 3:Landick Brothers
Episode 5:Seaick Brothers
They were but they still serve the exact same purpose. New toys*cough*I mean mecha that could combine with the main mech for a new modeGoseiger, on the other side, I cannot talk much about as I haven't seen it yet. But from what I remember, weren't they just some simple headers that could attack to the mecha?