Spelling and grammar. Typos are fine and easily overlooked, but I grew up in the days when diagramming sentences was actually required, and language has a science all its own. I don't care so much about proper breaking of paragraphs, or if you used a colon instead of a semicolon - but punctuation, capitalization and making the tense and voice of your statements agree with themselves isn't too much to ask in my book.
Detail, detail, detail. I have been accused of posing in George R.R. Martin levels of detail as far back as the opening days of Haunted Memories (In fact, it was Sullivan's comment to me to that effect that got me interested in GRRM to begin with. Yes, I do care about how well done the carrots were and if the capon was killed too old or roasted too long, thank you very much). We're playing in an environment where the only canvas we have is words, and as such the words need to paint a picture. This can be done with sufficient application of adjectives or adverbs, or it could be done as simply as a short meta-statement adjoining a pose. Vis a vis:
Sam looks at Max with the same sort of expression that he might have were she currently in the process of growing a second head.
It doesn't require much excess verbage, but still gets the point across that someone is looking at someone else strangely. A lot of context gets conveyed in expression and body language, and lacking that there needs to be something to indicate if the person's reaction/demeanor is positive, negative, perplexed or what have you. Something needs to indicate if an object in question is new, old, well used or well cared for. At the same time, a pose should be long enough to say what it needs to say; but it need not be longer. If all someone is doing is lurking in the background, wrapped in a burlap sack and making occasional sniffing noises that can easily and fairly be conveyed in a sentence or two.