General Observation: So, having a unique spin here was the name of the game. Not that you were no longer a Dragon-type specialist, but with many of the winners it does seem like being a Dragon-type Specialist was actually a secondary trait. I guess this is likely because of two reasons: (1) Being this is Johto we have two Dragon-type specialists who made the de facto dragon teams and (2) this is our first repeat Type and the previous one was for Sinnoh which HGSS shares a gen with thus the Pokemon available are similar (especially having access to Gen II Cross Gen Evos). So for those who've been around that long, you made your Gen IV de facto Dragon team there and voted which was the best (made better with Sinnoh not having a Dragon-type Specialist to compare to); now it's time for something a little different.
Pikachu315111: I thought my best chance had past with Unova Ice and a bit with LGPE Steel; I wasn't so sure with this one though. As I said, originally I was going for a Journey to the West team being it's the inspiration for Dragon Ball. so here what I was originally planning: Both Dragonite & Dragonair represented Tang Sanzang; Dragonair during the journey (an enlightened figure but hasn't fully reached his potential) and Dragonite at the end when he's granted Buddhahood (finally reaching his full potential and ascending). Lapras represents the White Dragon Horse, a banished dragon prince who ends up eating Sanzang's horse and makes up for it by becoming his new steed. Instead of Nidoqueen I had Nidoking who represented Sha Wujing, a former celestial that was exiled and turned into an ugly sand monster. Primeape was Sun Wukong. And then the problem came. I was hoping to use Mamoswine as Zhu Bajie, but it didn't learn Outrage as I was hoping. I like to sticking to my rule of the Pokemon at least having a Move of the specailty Type so had to rethink my plan. Looking over my team, I then realized each of them was also based on a Japanese Mythical creature, and though that excluded Kingdra and Ampharos, that did include Arcanine (and though Arcanine isn't a dragon, Shishi sometimes look draconic)! So with a change from Nidoking to Nidoqueen for balance purposes (and both being scaly monsters harkens to a dragon-like aesthetic, which just leaves Primeape as the sole non-dragon which most everyone's team had) I got my 1st place winning team.
Hugin: Large & In Charge, a good way to describe early Dragon-types depictions. And it mostly includes the usual non-Dragon dragons, with an interesting inclusion of Mamoswine. Maybe not a dragon, but certainly fitting your main theme so served as a boon. Makes me wonder if instead of, say Steelix or Gyarados, and had used another big mon like Snorlax would you have won.
Gryoine: ~
Which one of these is not like the other, which one of these doesn't belong~ Yanmega! Yes,yes, it's a dragonfly, and they're not the only one to have picked it. Still, it stands out, and while not bad in the sense for what people were looking for, I can still see how it also may have made some think twice. Your team is the only one which includes a Yanmega in the top 5, the difference being all your other Pokemon are Dragon-types or dragon stand-ins while the others had some more off the cuff choices. From what we've been discussing you'd think that then their team would be more voted, but I think your mostly dragon team with Yanmega being like "hello there fellow dragons" may have been the scale tipper.
Eeveeto & Imperial Magala: I actually see the same idea in both your teams even though you have three different dragon-like members: a popular stand-in (Ampharos & Tyranitar), uncommon but still fitting (Meganium & Nidoking), & an odd-ball (Dunsparce & Lickilicky). I think it's the Dunsparce that gave Eeveeto the edge; though we've reached the point where I think the teams start to just be primarily "Dragon" focused than having a stronger additional theme.
Some inclusions I liked on other teams: Noah3475 having all the Johto Starters, SturdyShedinja having Skarmory, & misterdarvus having Kangaskhan.