Hi Courtney -
We (as a company) are relatively new to Marketo, however, personally I am a veteran in many M.A. tools, and one of the priorities I had coming into this position was to establish standards, and one was the unsubscribe/opt-out. We are in the midst of redesigning our company website, so until that is set, I just took a minimalist approach to the layout and did everything in Marketo. We have an Unsubscribe and preference center that tie together.
Unsubscribe - http://pages.storagecraft.com/unsubscribe.html (if you click the check box, we ask a few lighthearted questions)
Unsubscribe Confirm - http://pages.storagecraft.com/unsubscribe_confirm.html
Preference Center - http://pages.storagecraft.com/preferences.html
Feel free to reach out with any questions. Hope this helps.