KyoryuGold was in the episode just to be defeated by Dogold. Ian was knocked to the ground even faster. Then Daigo goes Carnival and keeps up with him, even if he doesn't beat him. Comes monster time, the only thing that other members of the team did was getting beaten up and giving their batteries to Daigo.
And this episode's plot wasn't even supposed to be about Daigo. It focused on Amy and Souji, and yet he mostly took over during the battle.
Your point is that Daigo and Carnival shouldn't have taken over for the fight scene. Then the opponent they're facing should've been a MotW, because given what happened to Dogold in the last episode, it would have been really contrived for the Kyoryuugers to be able to even stand against him without any leverage. But then, people would've criticize the episode for not continuing the ongoing plot ie Dogold taking over Endolf and becoming exponentially stronger.
It's all right for Carnival to take the spotlight for said episode since it's a fight against Dogold. If future episodes have Carnival taking the spotlight in other character's focus episodes, and the enemy they fight doesn't even warrant it, also they can't get away without having an extra powerful boss fight, then I'll agree with you.
Gokiager and Zyuranger had a heavier emphasis on red rather than the whole team
SO I guess its a problem with sentai in general that Red is overemphasised
EDIT: Any of you guys have an idea why its like this? Or hell how to fix it
Even though Sentai shows are supposed to be a team show, being Red basically means being the lead protagonist. Being the lead and the most important in a team show would warrant having something other members don't, or basically being more special in some way(or else why are you the supposed
main hero, why is it not the guy next to you). And yes, get more emphasis. It is in every Sentai show even if Red didn't get an exclusive power up(he still will get the most emphasis) except if the show pointedly try to avoid it like in Go-Busters.
LOL I myself am not sure if it's something to be fixed. Especially when talking about hero shows. I mean, Go-Buster avoided that and look what happened. People were complaining that Hiromu is terrible Red and why isn't Ryuuji(Blue Buster) Red. They tried not to give Red extra emphasis, and he ends up being overshadowed by more active and likable characters, thus missing the point of him being Red.
I don't know about overemphasizing Reds, but I don't think emphasizing Reds more than the rest is not something that is simply supposed to be avoided.