Greg Valentine as a heel in the NWA. From the time he broke Wahoo's leg to the Piper feud in '83.
"Stunning" Steve Austin as WCW TV Champ. Neutral about the Stone Cold character.
Bret Hart's as a pro-Canadian whiner in the late 90's WWF
Rick Steamboat pre-WWE/pre-the Dragon. Great team with Youngblood.
Samoan Swat Team in WCW with Paul E. as their manager. Really well booked for about six months, till Paul E. left.
Randy Savage as an angry feral beast in Memphis. Though any Savage pre-WCW is pretty great.
The first heel run of the Lane/Eaton Midnight Express in JCP
Nikita Koloff's first run in JCP. Face turn + hair - steroids ruined him.
JYD & Jim Duggan as top faces in Mid South before their WWF runs as a lunchbox character and a drooling idiot.
The Flair/Arn/Ole/Tully IV Horsemen. Should never have been a Horsemen w/o Tully. Most natural heel in the IV.
Shawn Michaels first singles run in the WWF (the "Boy Toy" run w/ Sherri)
Heel Ted DiBiase in mid South. The Million Dollar Man character was great too.
Glen Jacob's brief run in Smoky Mountain as Unabomb. Only time he's been interesting to me.
Jeff Hardy as masked Will o' the Wisp in Omega. Never been a big fan of his, but this was fun.
Curt Hennig after the heel turn in AWA. Just barely edges out Mr. Perfect in my book.
Mike Shaw as "Makhan Singh" in Stampede. Brilliant as Singh, barely average before or after.
Jeff Jarrett's early heel run in the WWF. Making his Memphis heel persona more cartoony worked, for a change.
The first Stud Stable run in Continental, when it was just Jimmy Golden and the Fullers together.
I started to add Rick Rude's and Roddy Piper's names to the list, but couldn't decide on just one run. I cooled on Piper after his first couple year's the WWF, but he was a heat machine as a babyface or heel during the late 70's and 80's. His late 70's stuff with the Guerrero family in California is top notch,
I don't think I've ever disliked Rude. I wouldn't put the JCP run as my favorite (he was largely a tag wrestler with Manny Fernandez and Paul Jone's Army was just never a great stable). I don't know that I want to pick between the Florida/WCCW runs (both managed by Pringle), the WWF run, or the WCW run. Possibly the WCW run just because he had such great opponents to work with (Sting, Steamboat, Flair, etc.)