After looking at this list I have to admit yes, there was some pretty bad stuff that they tried, and if you blinked you probably missed the books featuring Red Wolf, Bloodstone, Black Goliath and the Cat (among others).
And if I had to name a couple of titles that I tried to like but could never garner much interest in, I would go with OMEGA THE UNKNOWN, LOGAN'S RUN and SPIDER-WOMAN.
Aug 1970 - Black Widow (in AMAZING ADVENTURES
Aug 1970 - Ka-Zar (in ASTONISHING TALES)
Aug 1970 - Doctor Doom (in ASTONISHING TALES)
Oct 1970 - CONAN THE BARBARIAN
Mar 1971 - Gullivar Jones (in CREATURES ON THE LOOSE)
Jun 1971 - KULL THE CONQUEROR
Dec 1971 - the Defenders (in MARVEL FEATURE)
Feb 1972 - WEREWOLF BY NIGHT
Mar 1972 - the Beast (in AMAZING ADVENTURES)
Apr 1972 - Warlock (in MARVEL PREMIERE)
Apr 1972 - Dracula (in TOMB OF DRACULA)
May 1972 - RED WOLF
Jun 1972 - Luke Cage (in HERO FOR HIRE)
Jun 1972 - COMBAT KELLY AND THE DEADLY DOZEN
Jun 1972 - OUTLAW KID
Aug 1972 - Ghost Rider (in MARVEL SPOTLIGHT)
Oct 1972 - THE GUNHAWKS
Oct 1972 - DOC SAVAGE
Oct 1972 - the Man-Thing (in ADVENTURE INTO FEAR)
Nov 1972 - NIGHT NURSE
Nov 1972 - THE CAT
Dec 1972 - SHANNA THE SHE-DEVIL
Jan 1973 - THE MONSTER OF FRANKENSTEIN
Feb 1973 - CRAZY!
Mar 1973 - Thongor (in CREATURES ON THE LOOSE)
May 1973 - Killraven (in AMAZING ADVENTURES)
May 1973 - The Living Mummy (in SUPERNATURAL THRILLERS)
Sep 1973 - Brother Voodoo (in STRANGE TALES)
Sep 1973 - the Thing (in MARVEL FEATURE)
Sep 1973 - the Black Panther (in JUNGLE ACTION)
Oct 1973 - Son of Satan (in MARVEL SPOTLIGHT)
Dec 1973 - Shang-Chi (in SPECIAL EDITION MARVEL)
Dec 1971 - It, the Living Colossus (in ASTONISHING TALES)
Feb 1974 - Morbius (in ADVENTURE INTO FEAR)
May 1974 - Iron Fist (in MARVEL PREMIERE)
Jun 1974 - the Golem (in STRANGE TALES)
Jul 1974 - the Man-Wolf (in CREATURES ON THE LOOSE)
Aug 1974 - Deathlok (in ASTONISHING TALES)
Oct 1974 - John Kowalski (in WAR IS HELL)
Dec 1974 - AARGH!
May 1975 - Howard the Duck (in GIANT-SIZE MAN-THING)
Jun 1975 - the Invaders (in GIANT-SIZE INVADERS)
Jul 1975 - the new X-Men (in GIANT-SIZE X-MEN)
Aug 1975 - SKULL THE SLAYER
Oct 1975 - Modred the Mystic (in MARVEL CHILLERS)
Oct 1975 - THE CHAMPIONS
Oct 1975 - Ulysses Bloodstone (in MARVEL PRESENTS)
Oct 1975 - ADVENTURES ON THE PLANET OF THE APES
Nov 1975 - Red Sonja (in MARVEL FEATURE)
Oct 1975 - BLACK GOLIATH
Feb 1976 - the Guardians of the Galaxy (in MARVEL PRESENTS)
Feb 1976 - Tigra (in MARVEL CHILLERS)
Mar 1976 - OMEGA THE UNKNOWN
Jul 1976 - THE ETERNALS
Sep 1976 - NOVA
Dec 1976 - 2001: A SPACE ODYSSEY
Jan 1977 - MS. MARVEL
Jan 1977 - LOGAN'S RUN
Feb 1977 - WHAT IF?
Apr 1977 - the 3-D Man (in MARVEL PREMIERE)
Jun 1977 - JOHN CARTER, WARLORD OF MARS
Jun 1977 - TARZAN
Jul 1977 - STAR WARS
Aug 1977 - GODZILLA
Sep 1977 - THE HUMAN FLY
Feb 1978 - THE MAN FROM ATLANTIS
Apr 1978 - SPIDER-WOMAN
Apr 1978 - DEVIL DINOSAUR
Apr 1978 - MACHINE MAN
Jan 1979 - MICRONAUTS
Feb 1979 - SHOGUN WARRIORS
Mar 1979 - BATTLESTAR GALACTICA
Dec 1979 - ROM