You cannot change the cursor in Acrobat - neither color nor the icon can be changed. You can change your document colors to make the cursor stick out more via the accessibility settings (Preferences>Accessibility>Change document colors).
If you are having a hard time seeing the white hand on a white document, you may want to submit an enhancement request for Acrobat here: https://www.adobe.com/cfusion/mmform/index.cfm?name=wishform
Karl Heinz Kremer
PDF Acrobatics Without a Net
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