Another problem often discovered at this stage is the presence of too many short sentences and paragraphs that seem choppy and abrupt. As a solution, try to develop these into longer, more graceful sentences. Formal writing generally utilizes longer sentences, so try using more compound and complex sentences. Using long sentences add flavor and variety to your writing, not to mention the fact that it also showcases your proficiency with words. You can also consider the word_count limit at this time and begin omitting unnecessary details that may only bog down your essay and make it unfocused. How can information be "condensed" while keeping the essence and maintaining the relevance of the essay? You can remove adverbs and excessive modifiers, as well as transform detailed sections to general statements.
The personal statement is also a great place to explain more serious problems, like less_than_ideal grades or test scores. Don't be afraid to write something like, "I don't test well" in the statement. As long as you can provide a good reason for you app's problems, it's okay to address them directly. You won't be able to hide it from admissions officers anyway, so providing a reason for problems is always preferable to ignoring them.