I don't honestly know how much description is too much. But I do know that every author has strengths and weaknesses. I know that the business of writing is filled with distinct individuals. I know that some authors can use massive blocks of description effectively and others cannot. It really depends on the author.
I know what I expect as a reader and reviewer though. I know that what separates the excellent writer from the good one is the drive for improvement. The excellent writers are never content with their writing. They constantly strive to provide the reader with better work and this is what the reader and reviewer want.
In the area of writing description there is always room for improvement. But there is also a basic reality to what the reader expects. Now, granted, the reader is an individual as well and some may be more tolerant than others, but here is the basic reality: The reader expects description to put them into the story, but not distract from it.
Some authors have their strong point in dialogue and action. Others have their strong point in description. Two authors whose strength is in description are T.A. Barron and Stephen Lawhead. They are masters at it. But both of their styles are wildly different.
T.A. Barron tends to have lengthier description sections and more often, but his language is so magnificent and easy to read that the reader hardly notices the absence of dialogue for a few pages.
Stephen Lawhead is a more balanced writer between dialogue and description, but he does have a strength is description. He is able to describe a scene vividly using unexpected details that successfully cast an image into the mind of his reader.
These two authors represent what I expect as a reader and reviewer. They use description effectively and are able to keep the reader's mind in the plot and run of the story. Scenes in writing are much like scenes in plays. The set (description) is in the background. It enhances, sets-up, and frames the scene, but it does not distract from the actors (characters.) This is what the reader expects from a writer in regards to description.