Deboth was pretty forgettable (except Candelilla and Luckyuro); and Kibaoni Corps may be the all time least intimidating, least threatening, and least interesting villain organization I've ever seen.
To be fair to Deboss, the show itself wasn't really trying to be super serious with them, and I think they accomplished what they were trying to do with them pretty well. The "main" villain(s) weren't the most amazing, but the generals were a lot of fun and pretty decent when the plot came to need them. Utchy and Dogold's rivalry was really well done, and it was nice to not have the rivalry be with the Red for a change (which is ironic because of the whole Daigo Sentai Daigoger thing).
Likewise with Kibaoni, Ninninger is... weird since it seems to both want to pay homage (or straight up rip off) a lot of older shows as well as blatantly play into the Yo-Kai Watch hype and see if it can cash in on it a bit. On that tangent, the earlier monsters of the week are pretty interesting and fun to me, for instance, but I find yokai to be a really cool topic in general - and similarly, having a feudal warlord has built in interest to the target audience based on cultural stuff.
Interesting? Barizorg did far more in 30 episodes of Gokaiger than Dokoku did in the entire series of Shinken.
Being interesting, enjoyable, or well written doesn't necessarily equate to having to have epic zomg plot significance.
Yeah, but he is supposed to be the leader. All he does is get drunk and whine about losing. I can understand if they needed to flood the river to release his army, but not for Dokoku himself. His being unable to go out onto land for more than 30 seconds makes him weaker than any Monster of the Week.
Main villain needing the world to be set up for their grand entrance wasn't completely new by Shinkenger's time, I'm pretty sure.
And even if he does, what's wrong with that? He was written well for a character in his position and his interactions with the rest of his forces always worked out nicely. That made him entertaining to watch and enjoyable as a character - far more so than your standard villain.
