Serve the song:
Play the parts that make the "SONG" sound best. Save the show-boating for the stage. Most of the time simpler is better when recording.
Sell the song:
Don't just play or sing, tell the story. This will improve your studio output and your stage show.
How can you have the best studio experience? Rehearse:
Know your material. Practice it until you can play it right over and over. Get your guitar sounds, harmonies, chord changes, and all the little details worked out before you start. This will save you valuable studio time not to mention improve your performances.