Exactly what everyone has already said. If you want to go above and beyond your box speed you need to go outside of your role. Be a role model, train and help others. When the TL or ETL ask you to stay, stay. Be adaptable. Do your job to the max, as well as you can.
As far as becoming a trainer goes...its a little more work, but you're just showing a new TM how to do their job. It shows that there's more to you than just showing up, doing your job and going home. You care enough to spend extra time and effort to help out new team members.