How can I edit how CiviEvent pricing is displayed?
You may be able to fix this with custom CSS. The following class is what you would need to adjust. Try setting the margin-left rule until the options line up. I have seen this when I am adjusting column widths on front end forms. 

.crm-container .crm-section .content {
    margin-left: 17%;
}

Note: my edits are usually in WordPress. There may be interactions with your Drupal theme that override this.