A writer has creative license to do what he wants. I give more leeway to those who actually adapt or reinterpret something. For example I'm more lenient on how let's say Christopher Nolan or Sam Raimi choose to adapt a character (usually rooted in what was popular in pop culture decades earlier) into another medium. Similarly, I want to see Neil Gaiman push his interpretation or reinterpretation of the Marvel Universe in 1602 as far as he can. If you're going to do an "Ultimate" alternate universe, creating a (quality) different and unique vision of the characters is to be commended.
However, if you're actually attempting to continue a character with decades of development and backstory....well first good luck coming up with something unique, original and interesting (which is unfortunately why formulas are so often recycled in comics). Secondly, if you make a character behave arbitrarily to achieve a plot point it will feel arbitrary. It goes back to that famous line, "What's the motivation?" If I can find something irrational or untrue about how a character behaves in a finite plot in a book I read, a play I see or a film I watched....you better bet it's going to be 20x more apparent in a character who has been written about infinitely.
Best example: Peter Parker selling his soul....err marriage to save Aunt May will never ever....ever make any sense or feel authentic. It felt like an arbitrary plot device--and an awful one at that--to achieve a narrative goal by the editorial board....to make Peter Parker single without having to cause him to go through divorce or being a widower. But Peter Parker would never make that decision given it is so unlike anything he's done in the last 40 years, not to mention his relationship with MJ in the last 20 years of comics. Another is Peter Parker unmasking himself in Civil War. It will never make sense for a character who wore the mask to protect his loved ones and saw what happened when a few enemies (Norman Osborn and Eddie Brock) found out who he was...Gwen Stacy dead, his Aunt May kidnapped and "killed," Flash Thompson in a coma, the loss of countless apartments and most of all the disappearance of his daughter (who btw no longer exists because editorial decided that ages him too much as well). He would never take his mask off on national television.
You can say that Stan Lee's, Gerry Conaway's, Roger Stern's, DeMatthis's, etc.'s Peters wouldn't, but JMS and Mark Millar's Peters would. However, if you read they're earlier stories from a few years prior to those events, you'd see they wrote him in line with earlier interpretations and not the idiot and tool he became.
Bad writing is bad writing. You can say "this is my version!" but if the writing stinks because it feels arbitrary, don't whine when the critics get their knives out in some cases.
