My essays mention two to three faculty per application and give each faculty member two sentences.
The first sentence was an enthusiastic "I would like to work with..." introduction.
If I review something right after writing it, everything is still too fresh in my mind, and I miss potential improvements.
After a few days and the dust has settled, it is easier to come back to an essay and read it while keeping a fresh perspective.
In some ways, waiting a few days before you revise brings your own revisions more inline with other readers' revisions.
Uc Berkeley Personal Statement Prompt
This brings me to mentioning (2): other peoples' revisions.
(2) is your chance to condense your research experience and present it in pros. First, your entire personal statement has to flow as a single essay.
Show how one experience led into the next, even if your second project wasn't "future work" from your first project (etc).
You will likely be space constrained and you need to solidly address the other bullets in the prompt.
The same principle goes with asking post-docs (as opposed to tenure-track faculty) for letters of recommendation: they just don't carry as much weight with admissions committees. Doing so can direct your application to faculty readers.