You have to go in terms of drawing and creative, the answer is...
Triple H and Kurt Angle from 1999-2001.
Retrospect, Triple H became top heel of the federation in the summer of 1999, doing evil acts and getting booed for them against the likes of Mr. Mcmahon, Stone Cold, Mankind, Kane, The Big Show and etc
Survivor Series 1999 Kurt Angle debuts and immediately gets alot of heat during his match with Shawn Stasiak and this would continue for the remainder of the year.
Triple H garnered more heat as he married the boss's daughter Stephanie Mcmahon, leading Vince and Shane to leave the WWF, meaning Stephanie Mcmahon was in charge, thus started the Mcmahon-Helmsley Era, Triple H and Stephanie constantly screwing The Rock, Mankind, The Big Show, Kane, basically running roughshot over the WWF roster.
These evil acts went way too far when they forced Rock to go against his best friend Mankind on a pink slip on a pole match in December of 1999, leading to Mankind... Mick Foley to getting fired.
Over the next weeks Triple H mocked Mankind in vignettes, and in January of 2000 screwed The Big Show to win the WWF championship back.
The heat was too much, the whole WWF roster lead by The Rock threatened to leave the WWF if Mick Foley wasn't reinstated, Triple H and Stephanie had no choice, it would be bad for business so Foley was reinstated and given a title shot at the Royal Rumble.
Triple H got heavily booed for his beatdown of Mankind in January of 2000, which lead to Foley turning into Cactus Jack to take on Triple H at the Rumble.
By the Royal Rumble Kurt Angle had been on an undefeated streak, and got major heat as Tazz "won" but it didn't count as he was choked out, while Triple H got major heat for beating Cactus Jack.
Kurt Angle's heat as a heel was so high he faced The Rock on Raw, where The Rock ended his undefeated streak.
In February of 2000 Kurt Angle won the WWF European championship, later at No Way Out 2000 he cheated to beat Chris Jericho for the WWF Intercontinental championship, he would celebrate it throughout the whole show. that same night Triple H ended Mick Foley's career, getting so much heat. Kurt Angle would go on to call himself Eurocontinental Champion
Kurt Angle would always mock city's and stressed using the 3 I's, Intensity, Integrity and Intelligence.
Triple H would cut promos attacking fan favorites and proclaiming himself The Game and that he is That Damn Good.
Triple H gained major heat for beating The Rock after Mr. Mcmahon screwed The Rock.
Kurt Angle would continue his heel work, and Triple & Rock would trade the title until King of The Ring where Rock got the title from Triple H ending that feud, while Kurt Angle won the King of the Ring.
Triple H would continue his heat, but against Chris Jericho, while Kurt Angle infuriated The Undertaker, leading to their respective matches at Fully Loaded.
Now during this period Stephanie Mcmahon-Helmsley would be talking to Kurt Angle, which would anger Triple H, by this point the top two heels for a long while.
This would escalate leading to Triple H feuding with Kurt Angle, heel against heel, because of Stephanie.
Triple H, Kurt Angle and Chris Jericho had a triple threat match for the #1 contendership at Summerslam, Triple H and Kurt Angle both pinned Jericho at the same time, leading to the Kurt Angle, Triple H, Rock triple threat match at Summerslam 2000.
The smackdown before Summerslam Kurt Angle crossed the line and kissed a semi-conscious Stephanie.
Rock ended up winning because Triple H and Kurt Angle were so focused on each other.
Triple H and Kurt Angle continued their historic rivalry, Kurt Angle had so much heat they had to turn Triple H babyface.
Stephanie ultimately choose Triple H at Unforgiven 2000.
The Triple H and Kurt Angle storyline continued even after their Unforgiven match, at No Mercy Kurt Angle was going to face The Rock for the WWF championship while Triple H faced Benoit because of what he did to Stephanie.
Triple H was not pleased with Stephanie managing Kurt Angle, Kurt Angle won the WWF championship.
Later on Triple H was turned heel again for Austin as the Austin storyline wasn't working since his return, Triple H gave it new life and made it successful.
Triple H and Kurt Angle were once again both heels, Kurt Angle as the WWF champion and Triple H as ruthless heel.
At Armageddon 2000 Kurt Angle retained his WWF championship against The Undertaker, Rikishi, Rock, Austin and Triple H in the hell in a cell match.
Triple H returned in January of 2001 costing Austin his WWF championship match against Kurt Angle.
Out of the blue upon his return Triple H became #1 contender for the WWF championship against Kurt Angle at the Royal Rumble, Triple H and Kurt Angle were once again in a feud, this time for the WWF championship. Austin interfered and helped Kurt Angle retain the championship.
Kurt Angle was such a huge heel that he was expected by many fans to defend the WWF championship at Wrestlemania 17(The original plans were Triple H vs Rock vs Austin, but Triple H stepped down making it a one on one match, had the WWF been organic about it Kurt Angle would've defended against Rock/Austin/Triple H or Rock/Angle culminating the 2000-2001 season)
Throughout the entire 2000-2001 season Rock/Austin had been feuding against Triple H/Kurt Angle.
Funny that you say Rock/Austin type heels as they were faced by this duo, as this all culminated at No Way Out 2001 in a double main event, Triple H faced Stone Cold in a 3 stages of hell match while Kurt Angle defended his WWF championship against The Rock.
Rock became WWF champion while Triple H beat Austin in the match.
Rock would go on to feud with Austin leading to their Wrestlemania 17, however Kurt Angle was apart of this rivalry throughout most of it, being the reason for the problems(Caused Rock to get stunnered, gave Debra ankle lock, etc)
Triple H would feud with Undertaker leading to Wrestlemania 17.
Kurt Angle was without a match even though being a huge part of the Rock/Austin story, and was given Chris Benoit to face at the last minute.
After Wrestlemania 17, Rock left, Kurt Angle was nonsensically placed in mid card despite being a huge draw, Triple H was relegated to Intercontinental champion despite being the biggest draw after The Rock and Austin was forced into the title scene and pushed as their top heel despite not drawing much heat.
It could only be a disaster with those issues.
Triple H got injured in May of 2001 and didn't return until January of 2002 as a babyface, while Kurt Angle was kept in mid card for no reason despite being the top heel for almost 2 years.
Kurt Angle was turned babyface in the summer of 2001, having the Alliance and Austin as the heels.
Kurt Angle was turned heel yes, but Triple H returned as a babyface.