Always remember, a thank you is a nice touch, but it can be a great strategic move. Include anything you think of after your interview that you wish you had said in retrospect (not too much though, keep it short and sweet).
If there were any concerns shared about your suitability, address them and reiterate your reasoning behind this potential weakness not being a problem and your suitability for the role.
Finish by highlighting your three top experiences and qualifications and how they would benefit the company from what you learnt during your interview. Reiterate information you learnt and your increased interests and determination, promising to deliver in the role, as we are sure you will.
