I’m a big fan of Adobe Acrobat Forms, I faced different cases in my work, other departments asked me to design a PDF form but a dynamic, the content in the boxes can be expended or shrink depends on the data. In Adobe Acrobat these kind of forms called Flowed layout. I thought it will be a tough task to do such thing, but after playing around with Adobe LiveCycle, it was easy and almost straight forward.
The most important part to decide which pages are flowed layout and which are positioned, and then everything will be in few clicks. All you have to do is to make the Page layout Flowed and wrap all your fields within a subform with a flowed layout, and for each field in the layout tab, select expand to fit property so the field are expandable.
Find this test PDF, it will explain everything also I added how to add more Table rows dynamically into a PDF form.
Note: You have to save your PDF file as Dynamic PDF in order to make it expandable.