These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
When Leinil Yu was providing artwork for the series, he continued to include Iron Fist in his classic costume even though the character had debuted a brand new costume a few months earlier in The Immortal Iron Fist, and constantly featured Howard the Duck in group shots of various heroes not in the team.
Creator's Pet: Luke Cage for Brian Michael Bendis, who's run on the book saw him go from Hero For Hire to leader of the New Avengers, and is one of three characters (The others beingWolverine & Spider-Man) to remain on the team for the entirety of the first two volumes. To a lesser extent, Jessica Jones, who was merely a supporting character in the first volume before becoming a full fledged member of the team following Dark Reign & actually was created by Bendis.
Subverted, however, in that many fans don't mind having those two at the forefront.
Ho Yay: When the embarrassing truth came out that Jessica Jones had a crush on Peter Parker when they were in high school came out, Spider-Man attempted to reassure Luke Cage that he had no designs on his wife. He then went on to ask if the way were clear to Iron Fist...
They Changed It, Now It Sucks: The reaction a number of "old school" Avengers fans had, with the initial line-up featuring only two classic Avengers & the shift away from the global level threats the classic book dealt with.