Gen 1: Favourite : I actually like all of the Gen 1 E4 but, out of them All Agatha and Lance stand out the most. Ghost Crone or Dragon Tamer....yeah I'll go with the Dragon tamer just this once(Unless Drayden's part of the E4, Drayden outranks everyone on this list)Aside from that, wee Dragonite Spam. His Gen 2 team could've been better and his Gen 1 team could've included Arbok(Though Agatha used it)Rhydon(Though it's Giovanni's Ace)Onix(Bruno used one)and Charizard(He uses one quite frequently.)Any of those could've filled up his team(aswell as a Seadra)but whatever, in yellow he's got the triple coverage Dragonite so eh. Lance is the cape lord.
Least Favourite: I actually like Bruno;he could have a really interesting character but the fact of the matter is that he rarely appears and his team is bland as fuck. He could've had some kind of Ground/Fighting team(As he seems to be fond of Mountainous based pokemon instead of just the fighting type)With His Current Fighting Types, Sandslash, Poliwrath and Primeape/Rhydon/Onix. Would've put up a much better fight. Atleast he trains in a room full of lava I guess.
Gen 2:
Favourite: I really wanna say Koga cuz he's a fucking Ninja, but Karen's actually the coolest of the Johto E4(Sorry Koga man.)She pretty much gives the fuck you to guys like Silver&Paul and all of Smogon and just uses pokemon she likes. Then there's the whole "Dark type" shming she has. Gengar fits the dark typing pretty well though a Sneasel...or even a T-tar if the level curve wasn't as horrible as it currently was could've been interesting. Sad.
Least Favourite: Will: Who's this guy again? Like this guy is the least memorable E4 member of them all. Sure he looks goofy and has an interesting arena, but Bruno the guy who you face right AFTER him fights in an arena full of LAVA(IDK how they got that in there. And he uses barely memorable psychic types;WHY DOESN'T HE HAVE A FUCKING SLOWKING. Like;Xatu,Exeggutor, Jynx, Slowbro, Slowking would be much better than having 2 Xatus. Karen has an Umbreon, Why doesn't this guy have an Espeon?
Gen 3:
(Honorable mention to Drake for being a Pirate Captain/Dragon Tamer)Phoebe's my fave here, ghost type specialist in a gen that introduced some really cool ghosts. In particular my favourite ghost type;Dusknoir is her Ace in ORAS and I love it. She also has that creepy ghost girl in there.
Least Favourite: Glacia: Let me say it here, I DESPISE GLACIA. She has to be my least favourite E4 member of them all. Will may be very forgetable but he's alright. THIS FUCKING WOMAN IS A DEMON. Let me tell you a story: Around this time last year, I did an Emerald nuzlocke and managed to get to the E4;I got to Glacia and guess what? She has 2 Glalie's. Now I expected them to be exact replicas of each other so I payed the second one no mind attacked with my Azumarill;who by the way was my trump card against Drake with it's ice beam. WORST IDEA EVER;It exploded on me....and with it went my Azumarill. But that isn't the end of it, OOOH NOOO. In a recent nuzlocke of ORAS; her Walrein got off 2 consecutive sheer colds. I AM SO DONE WITH HER. (Excuse my rage, but she's pissed me off to no end)
Gen 4: Eh, Gen 4's E4 isn't that memorable though Cynthia has all the coolness needed for a League on her own. By default t's Flint cuz he's cool and uses some cool fire types in Platinum though his team in DP was anything but fire.
Least Favourite: Lucian, IDK this guy just feels odd. Reminds me of Will but even less memorable. 4.8/10.
Gen 5: The brothers Grimsley. This guy is all kinds of cool;A: Uses Dark types B: Looks swaggy as fuck C: Is a Gambler D: Uses Bisharp, Scrafty and Krookodile. This guy is just wow. 10/10 would face again.
Least Favourite: I can't actually pick here, all are cool but out of them all; least fav is Marshal and that's only because the other 3 are just as cool and fighting is my least favourite type out of them XD.
Gen 6: Wikstrom: His team and theme is just that cool. He's kinda lacking in substance but he's a knight with an Aegislash and Scizor. Now if he had a Lucario instead of Probopass his team would be badass amongst the badass.
Malva: She reminds me of Giovanni; only weirder and less forshadowed. Like you face Giovanni multiple times throughout the game but Malva appears at the League randomly;speaks 8 lines and faces you. Her team is interesting but her Talonflame doesn't have Gale Wings to take advantage of leaving much to be desired.
Honorable mention to Siebold for being as cool as he is.