Kaldor Draigo because he lives in the the warp which is an impressive feat, Justicar Thawn because he is immortal and badass and Rafen because he managed to kill about 4 Fabius Bile clones.
The SW have a whole company that has lived in the warp for over 10,000 years. Draigo does warp dust. I saw it on youtube.
Chapter Master Sarpedon of the Soul Drinkers. Garviel Loken, Captain of the 10th company of the Luna Wolves/Sons of Horus. Sanguinius, Primarch of the IX Legion and all successor chapters. Lord Commander Dante, Chapter Master of the Blood Angels Chapter. To only name a few.
The Eye of Terror actually. There's an important difference between the two. The Eye of Terror is infused with Warp energy and is a realm in which the immaterium bleeds through into reality, but is only extremely dangerous. The Warp is a place of pure energy, completely incomprehensible and is utterly hostile to all mortal lifeforms to the point where they will be obliterated if they enter it physically, without the protection of Chaos sorcery, a daemonic patron or Gelldar field. It's just a shame codex writers can't remember that fact.
Vulkan the Forgefather. I may be a Templar at heart, I can not deny my respect for him, and for the sons of Nocturne, when I am not fielding my army as Templars, I field them as Salamanders, out of respect, and my love of flame weapons, I even used a Terminator Close Combat squad equipped with Thunder Hammers. They were known as the Forgebrothers in honor of the Salamanders And, how can we forget about High Marshal Helbrecht. Honestly, he is just kind of awesome, I mean, the dude loses his arm to a Necron Phaeron, goes on a crusade to repent, then whoops the same Phaeron's shiny metal ass in single combat, and destroys the Necron ship from the inside out. It's kind of cool
One of my Favs is Solomon Spoiler Solomon Demeter was the Captain of the 2nd Company of the Emperor's Children Space Marine Legion. Demeter was somewhat atypical for an officer of the Emperor's Children, being possessed of a steak of individualism and recklessness that made him stand out from his peers. During the dark days of the corruption of the legion, his individual nature, along with a twist of fortune, led to him becoming virtually the only senior officer of the legion not to succumb to the temptations of Slaanesh.
Emperor, Dorn, Sigismund, Helbrecht, Grimaldus! Ofc I also like Farsight for not taking S*** from the ethereals, Catachans IC in general cause they are Badass! And that's about it. While I have respect for most of the other chapters chars I cant say I admire them but I do have a certain curiosity to know who is Sanguinor.
Gabriel Angelos, chapter master of the Blood Ravens. An excellent example of what a Space Marine should be; smart, resolute, noble and heroic but with flaws and limitations. (Unlike a certain blue chapter master). He (if DoW II Ret is canon) single handedly (tried to) beat the shit out of a daemon prince of Khorne (but then got stomped) and then goes on to shoulder the responsibility of redeeming the bloody magpies in the eyes of the Emperor. He isn't a mini primarch, he can't kill legions with mind bullets, but he does every damn thing he can to get the job done.