Is possible for me, as the owner of a team account, to:
Basically, I want to transfer ownership of my team account.
You are able to make another member an owner by switching over to the Team and visiting:
https://cloud.digitalocean.com/settings/team/
Please click on More => Change Role on the member you wish to make an owner. You'll receive an e-mail to confirm that you really want to make that member an owner. Please click the link in the e-mail and that'll confirm the change.
Once the other member is an owner, click on More => Leave Team next to your e-mail. An owner won't be able to remove an owner, so you'll need to remove yourself in this case :-).
Once you leave the Team, the Team Account will disappear from your account so you will no longer be able to access it or make any changes (including billing changes), so please make sure the card has been removed and that they set a new card, else you may be billed for any charges they rack up.
Thanks. That is as I thought and hoped. I'm only a team member on a bunch of projects, so don't get to see that part of the UX.