From the previews for the next Den-O episode, I have a feeling that the last Imajin will pwn the other three when it comes to the opening sequence dance number
The only gripe I have with Den-O is that they should give Naomi more screentime. Seeing her in that costume can make anyone start at a climax
And more screentime for Sword Form too
As for Geki, Rio will "probably" become part of the Geki team, since the Lion beast aura he emits looks like it can replace Jan's tiger to form an alternate Gekitouja. Kung-fu schools usually have branch schools, either loyal to the main/head or just waiting for the time they can usurp the power, so it is also possible that Akugata has other baddies aside from Rio and Mele, that are stronger and badder.
BTW, do you guys have the full version of Gekiranger's opening theme?
I still can't believe Ran was in Garo