I assumed it was just Ryoutaro, although I think Den-O could win either way.

Den-O's crossing into Clock Up Kick the Sun territory, you know that right?

If having a few extra belts is that, then what's having a highschooler tell Fourze which new toy to use?

Wait, you're trying to compare having 6 versions of one character existing at the same time to Kengo?

Try? I'm pretty sure that's what I did.

You're absolutely right. Being possessed by six different Imagin, each with a different power, and being completely useless without them. And OP with them. Is exactly the same as being helped with switches.

Kengo can only help Gentaro via the Radar Module, he's not exactly on the battle field for this fight. OOO fought by himself in the first tournament without the help of Ankh.

Edit: Actually, since the Rabbit Hatch has been destroyed, I don't think Radar can exactly help unless Kengo still has the Astro Switch Kaban

Again, Liner Form exists.

My whole point was if that's the case, and all the Imagin have belts, than anytime OOO's is up, he has to have the power where the Gatakiriba clones can turn into the all the different forms.

Personal thought:
And since there 9 medals per Greeed, 3 of each type (head, body, legs), and based on the Movie, it's safe to assume that there can be 3 of each colored form (3 GKB, 3 LTT, 3 Shouta, 3 Tajador, and 3 Sagoza). Plus his Puto-form.

Is that really what we're sayin?

Problem with your awesome theory is that as of SHT he seems to only have one of each set plus a spare TaToBa set, and the Super Medals. That would be awesome though lol.

But yeah, if Ryotaro thought of going back in time and gathering the other Den-O Belts or if Owner gave him the extra belts, it can happen.