Some might need to play with less pressure, while others may need a reminder to play more boldly. The variety of issues to consider here is infinite, as they are specific to the individual and they may evolve over time, depending on what is top priority at the moment. Choosing more than one item to consider, however, would only burden your abilities to concentrate, so choose carefully. Don't forget that your performance is the time when you can finally share with your listeners what you have worked so hard in the practice room to achieve. This is a time of joy and not a time for correcting errors or other faults.
Players tend to be too self-critical in performance.
The practice room is the place for that. The concert hall is the place for celebrating the music. Let your emotions for the music be present. Don't allow minor details to obscure your feelings about the music. Let your excitement for the music be present.