Here is my list (arranged according to Mugen engine aka from Dos to Mugen 1.1):
Dos Era:
VK: His Gouki was the best character in the old Dos Mugen version 2000.01.01
MystikBlaze: His Evil Ryu is a beast in Dos Mugen era
Gargoyle: His Capcom vs. SNK's Geese Howard can defeat overpowered characters like Evil Ryu by MystikBlaze, Evil Ryu and Evil Ken by Reu back in the Dos era
Sunboy: I like his Black Heart
Spolde: I like his Iceman and Strider
Big Eli King: Best Venom he has ever created in Mugen, as well as Dark Chun-Li
Reu: He was the greatest Mugen legend ever and was from the same country as me
SystemID & Ckenni: I like his Sogetsu Kazama
KGenjuro: created great Samurai Spirit characters, his Ukyo Tachibana is pretty fun which I played as in my first Mugen game
NeoGouki: I like his Joe Higashi which I have played in my first Mugen game
MMR: I like his Marco Rodriguez
3ha: His Bishamon made me like Bishamon in Vampire Savior and the cool part is that he can transform to Galford and Jin Saotome's Blodia mode
Orochi Herman: I love his Setsuna, Shinnosuke Kagami and Shadow Dio.
Third: He made several fighting game boss characters especially his Shinnosuke Kagami was my best favorite. I hope he would released his Original Zero which was one of his WIP and look promising at that time
Jun: He created a cool looking Gouki edit which was Ogre who has many different moves from other characters
MIT: His edits are interesting such as Chris-Type-M and Yasanagi
Yong Ming: Another Mugen talent from my country who created some King of Fighters' characters
Sander 71113: I like his old version of Iori Yagami that had Mature and Vice watching the match.
O ilusionista & Ethan Lives: I love their Special Operation's characters
Rou Hei's Mugen (Old Window Mugen):
Gonzo: He created several kof bosses.
Ahuron: All his characters are pretty creative.
Warusaki3: Best Capcom vs. SNK 2's characters that he ever created. Even though I am no fan of edited characters, he managed to make me likes them which his skills in creating Capcom vs. SNK 2's style characters. I like his Kuroko, Hayato Kanzaki and Jill Valentine. He created some other characters that aren't Capcom vs. SNK 2. I like his Final Dio even though I did not play Jojo Bizarre Adventure before and would love to main him as my first character if I have a chance to play that game.
H': Same as Warusaki3, I heard he gave Warusaki3 his resources for his characters such as the power gauge. I like his Sagat and Red Arremer.
Y.Y: His Hol Horse was the reason and his Robo Ky are pretty Innovative as well.
GM: created near accurate creations like Street Fighter 3 and Garou Mark of the Wolves.
Umihei: Before Rajaaboy create Urien, I always use his Urien.
Abuhachi: Same reason as GM and he created many boss characters as well. I love his Ryuji Yamazaki.
Tora: His Geese Howard is my sole reason, he has a hidden mode that can activate his Nightmare Mode permanently.
HSR: He created Setsuna, my best favorite Last Blade's character.
3ha: He created characters for window Mugen as well which play as innovative as always. I love his Zangeese and Lenja most.
Beximus: Even though he did not create any of my favorite characters, I like what he is doing. His Capcom Universe: Nexus of Heroes is my best favorite Mugen game of all.
Mouser: I like his MvC2 characters especially he created Ryu, Ken and Gouki.
Sekirei: His Ryo, Robert and Takuma are the reasons, as well as his Geese Howard.
Ikaruga: After he started to create characters from source game like Kof98, Kof2002um, KOFXI etc, I became a fan of him. A pity that his characters cause problem for Mugen 1.0/1.1 engine. He has no issues in Rou Hei's window Mugen.
Ohgaki: He created many great Last Blade characters as well as edited King of Fighter characters. I like his Seiryu Kaede best.
Hal: Just like Ohgaki, he created great Last Blade characters as well which rival Ohgaki's characters. His Awaken Shinnosuke Kagami is my best favorite. Sadly that he often reject me to follow him in his twitter for no reason.
Muteki: Created all Guilty Gear XX characters. I like his Robo-Ky most.
Akutagawa: I like his Order-Sol most.
Neat Unsou: I have not played Sengoku Basara-X until I play as his Date Masamune as my first Sengoku Basara-X character and find him fun to play as.
Gal129&Rei: He created many types of characters such as Capcom vs. SNK 2's characters, Vampire Savior's characters, Sengoku Basara-X's characters and so on. His characters can be glitchy if used in newer version of Mugen. I like Oda Nobunaga which makes him become my second main character if I play Sengoku Basara-X.
Doogiedoo: Blade is cool character from Warzard and fun to use in Mugen.
Mugen 1.0:
Pots: I like his Geese Howard and he inspired many Mugen creators in his creations.
Divinewolf: He created Sagat and Gouki. His characters are still playable in old window Mugen.
Jesuszilla: I like how he aims to create characters as accurate to source fighting game although I don't really like his attitude in replying to members' threads sometimes.
Vans: He shares several information about Mugen creations especially his KOF characters.
Koopakoot: I like his KOF Interactive tutorial which makes me get interested in wanting to create KOF characters. I wished many Mugen creators would create characters' tutorial like him.
Websta: I like his Neogeo Battle Coliseum especially his Kaede who is my main character in Neogeo Battle Coliseum. I hope he would return to complete all Neogeo Battle Coliseum characters.
Rajaaboy: I like his Street Fighter 3's characters. His Urien is god like to me.
R@ceAkir@: I like his Rasetsumaru
Falcon Rapper: I like how he converts KOF characters into Infinite style characters
Shiyo Kakuge/Tatsu: His stages and tag patch that he made for Mugen are frickin cool
RedHot: He is trying to convert all Marvel vs. Capcom 2's characters
I am always looking forward to his creations
ShinZankuro: I like his works. His Gouki is my best favorite in his MvC style.
Omegapsycho: I like his Mortal Kombat characters. I am looking forward to all his Mortal Kombat characters especially his Chameleon MK2 style, Shang Tsung MK2 and UMK3/Trilogy.
YamoriX: I like all her works
Mugen 1.1:
Mr. Ansatsuken: His Gouki is my best favorite
I hope he return to add Street Fighter V and Tekken 7 mode to his Gouki
Others:
Borewood: He helped me with Orochi by Orochi Herman's problem in Mugen Free For All forum and his topics in forum are pretty interesting
Kong: Amazing Characters' Sprite ripper and he helped me with a character's problem
OldGamer: I like his stuffs and his Mugen tutorials on stages, lifebar, screenpack and so on
Farram: I like his Mugen Roster and videos
Swagga Kings: I enjoy watching his Mugen matches where he challenge against his friends
Thats' all, I hope I did not miss anything
by 
the boss)
NamelessOnlinePlayer, yolomate & I-Skorp-I : I love that you are always here to give life to the forum.
:
and he is able to deal with all those long-time MUGEN e-bashing/e-haunting/e-trolling/e-bullying/e-pissing-you-off-on-purpose bad deeds with ease, oh man I just want to be immune to those reckless and heartless MUGEN people like how chuchoryu-sama does, yet I fail big time............ 
......
):
