For aesthetic reasons: Bulbasaur (favorite), Turtwig (least favorite)
For in-game reasons: Torchic (favorite), Tepig (least favorite)
For competitive reason: Chimchar (favorite), Squirtle (least favorite)
EDIT: And Piplup gets an honorable mention because he is just so dang cute. And Empoleon actually kicked some butt when I used him for my Grass/Steel team.
Jumping on the Fenne-Bandwagon
My most favorite is Piplup. First of all, I love it's typing; water/steel; great coverage and resistances. Second, I adore Dawn's Piplup in the anime. He is super cute and adorable with a swag!~
And for so many reasons, Piplup is one of the greatest pokemons ever (that includes it's evolutions).
My least favorite is Tepig. Like someone else said here, it had a lot of potential but Emboar totally ruined it for me. Tepig has a great design until it got weirder and messed up. Emboar looked like a roasted Snorlax.
I was a bad girl one time...and now I'm gonna pay for what I did forever and ever and ever.
Register my FriendCode: 4900-4430-5335
Thank you. Chickorita is a pathetic excuse for a starter
Favorite: Bulbasaur. I don't know why, I've just always loved Bulbasaur. It's a great Pokemon with its evolutions, good design, good personality in the anime, and I love grass types (I also like water but yeah).
Least Favorite: Chikorita. A real disappointment. Its moves sucks, completely useless, bad designs and evolutions, it's a disgrace to grass types.
Black 2 Team Members:
Wooly (Ampharos) - Level 44, Male
Matt (Umbreon) - Level 56, Male
Horace (Gyarados) - Level 50, Male
Zero (Blaziken) - Level 61, Male
Sawsbuck (Sawsbuck) - Level 45, Female
Nova (Lunatone) - Level 50, Genderless
Signature is a WIP for the moment.
For now, I have claimed: Mewtwo, Member's Card, Wide Lens, Honey Gather, and Psystrike.
Favorites: Piplup (my top favorite), Chimchar, and Squirtle
In between: Cyndaquil, Charmander, and Oshawott (I do like them, it's just that everyone uses them. XD)
Least favorites: Tepig and Chikorita (overall they're just not good fighters to me. and Tepig has the worst the worst Fire/Fighting evolutions in my opinion)
Look Forward, Team Rocket!
Also I claim Piplup in the Claim a Pokemon thread =)
My favourite is Samurott, but I've gushed about it plenty of times in other threads, so I'm not going to here xD
Oddly enough my least favourite is Oshawott, but if I must choose another line, then Chimchar. The whole line is hideous, and I'm bitter about how GF catered to Infernape's every whim in terms of stats and movepool.
Favourite: Chikorita. Screw everyone who hates this line, it was awesome in the anime, makes a good wall and is one of my most nostalgic pokemon. It's just unfortunate in the generation it was released at it is weak to the first two gyms and isn't SE against any in Johto. See "Tie One On" and Meganium should seem a lot more bad ass. Plus, I believe Ash's Bayleef only lost twice after evolving.
Least Favourite: Tepig line, just ugly imo.
If you are a fan of the Star Wars Battlefront series and dream of seeing a third installment, watch this video: https://www.youtube.com/watch?v=bd2fq6Id6AE.
All hail the King in the North!