How to sign an agreement before sending it?

We are using the Adobe Sign API to create agreements using a collection of templates. We want our staff to review the agreements before sending them. Sometimes our staff has to sign agreements before sending them. We are unable to do this and we have explored many solutions:

1. After our service has created the agreement with the API, edit the agreement, add a signature field and sign it right away. This does not work because signature fields cannot be set prefill or have a default value.

2. After our service has created the agreement with the API, edit the agreement, add a text field and sign it right away. This does not work because text fields have no cursive font option, nothing looks like a signature.

3. After our service has created the agreement with the API, add a recipient to the list of recipients in the Adobe Sign UI, add a signature field assigned to this new recipient and send the agreement. This does not work because we cannot add a recipient to the list of recipients.

4. Use fill & sign. This does not work because we use the API to create complex agreements with multiple templates, a lot of prefilled data, etc. It's too much work for our staff to build the agreement with fill & sign.

5. We can't include the signature of our staff members in the PDF templates because we have too many staff members. We'd need a large number of templates for each staff member.

Is there a simple way of solving our issue? Either being able to sign an agreement before sending it in the Adobe Sign UI or allow our staff to add themselves as a recipient to the agreement and sign it when it's their turn.

Thanks, Simon