Use one compound field or many fields, which is the good practice?

I got a problem when developing a compound field (Drupal 6, cck 2). It has an Imagefiled, a few textarea/textfield/checkboxes, etc.

I realize that I must allow users to upload multiple images. Unfortunately, the compound field as an entire field can be set to allow "unlimited" number of values , but not the individual field (the image field) in the compound field. I step into module files and database and did some research, and found it is hard to achieve this by using "Drupal Way".

It brings another question, when it comes to choose from one compound field or many fields, which is the best practice usually?

For my case, instead of using a compound filed, I can use multiple fields. Compound field is better in some cases. Info like "Education background" is a perfect example. Education background is consisted of one or more degree info, each degree info is consisted of degree name, year of graduate, institution name, if graduated or expect to graduate, etc.

But what about if the compound filed as a whole is expected to only have one value? Shall I still use compound field or simply using multiple fields (using content CRUD API to programmatically create fields) ?

Thanks,