Enhanced custom contact field functionality

When making custom contact fields as a dropdown list, I've found these two functionalities would be super helpful for more customization:

• It would be great to be able to have a dropdown of pre-selected options as well as a free-text response box if none of the pre-selected options fit

• As well as the above, it'd be great for it to be flexible to have the ability to have a multi-select dropdown (if there are multiple selections that are relevant for a contact)