I really liked that about BOTH BW protagonists...(the apparent ability to relate with them that is.) My reasoning behind the appearance of Hilbert/Hilda is quite simply that Unova is the first (Game Freak Title, before anyone brings up Orre...) region to represent an "American" environment. As such, the protagonists and other trainer classes there look more "Basic" to us.
Hugh (Azery, Jericho) is my favorite rival of them all. Often misunderstood by the community as someone who has a forced storyline and is only written to appear like a rage monster, Hugh is the first rival to not make it a clear goal to be stronger than you. If you're a "Genwunner" or the like, you don't appreciate it much at all, and if you like the "friendly competition" based rivals of Gen 3, 4, the original Black and White, and 6, then you don't understand the reasoning behind Hugh's angst. Instead, your rival actually is given his own story arc that extenuates beyond trying to get to the pokemon league before you do, or trying to understand what real "strength" is. He and Silver fall under the category of "vengeful" rivals, while Hugh's reasoning makes it seem like he's after "real" redemption. Yes, he also has the silly catchphrase and I'm a sucker for those, but the touching moment when Hugh finally tracks down that Purrloin aboard the Plasma Frigate, only to find that it's forgotten it's past and has evolved into a Liepard. ...OH...So Good...
They have "snow classes" in DPPt?....neat.....
The next three classes I would use are as follows:
(Female) Veteran - BW/BW2 - This trainer's MO is -all- about life experience and developing a real "lifetime" bond with your partners. My favorite "Veteran" actually comes from Kalos, and her dialogue is surreal. She talks about her lover leaving her behind and how much despair life can bring, as well as how it can mold you into a tougher trainer. If you're not prepared for her Tyrantrum (for some...reason) it can really cause problems. The female veterans actually starkly contrast to their male counterparts. While the men cheery and typically happy with their partners and lives, the females are rather down in the dumps, or more determined. Like Hukuna said above, the Veteran doesn't play games. The other thing that makes this woman a winner in my book is that she, like I, is an Adult. These people are "veterans" at not only pokemon, but at Life.
Gym Leader Sabrina - HGSS - Gameverse Sabrina is a little more ....human.... than her anime counterpart. Her poses are full of attitude and she even has relevance outside of her gym. She features as a movie star in Gen 5 as well. I don't actually see myself -using- this sprite per se, but I've always thought the Saffron City gym leader was pretty neat.
(Female) Ace Trainer - DPPt - The trainer class Florinia is based off of. ...Nothing else to be said here.
Trainer classes I would -NEVER- use are as follows.
Sinnoh Champion Cynthia - DPPt/BW/BW2 - I don't connect with Cynthia very much. I have yet to figure out her true strength (and I really need to get on that) and I only know about her from reading up. She -is- a pretty neat archeologist type figure, and that's something I have looked into myself during my college career, and she's probably easily one of the most fearsome women in the Pokemon franchise in terms of appearance. She exudes power. I...I don't exude it, I have to demonstrate it first.
PKMN Trainer Red - HGSS - ... I'm not going to sound like a hipster here. Red is an amazing example however, of someone who receives just a little too much hype for what he offers to the table in terms of storyline. In Generation II, it -was- extremely neat to get to actually battle the protagonist that made you fall in love with the franchise. The battle itself was tough in terms of having to really grind to be able to even compete with Red on top of Mt.Silver but.. I'm always a bit of a renegade when it comes to the argument of "who is the toughest dex holder of them all" There's always the fact that as a kid, I -BEAT- Red. If I'm going with personal canon, that would make Gold/Ethan/Kris the toughest trainer up to that point. In the Pokemon World Tournement, I beat Red...in a tour set up with all of the toughest trainers in the land, which would make ROSA the toughest trainer of them all. Too many holes to make Red seem like a viable sprite to me. (I'm also not much of a Genwunner, too.)
Either protagonist from Sinnoh -- Lucas is the default sprite on PO in general. Default is boring.....and I don't really care for Dawn much either. Most of this however is due to not playing the game.