hook_schema / hook_insert versus hook_field_* / drupal_execute

hi drupal community,
it's very hard to get information and answer about this kind of issue

I want to programmatically populate a new content of my own ( job status extracted from SAP).
But what is the better way to create and also access this new content ?

I think there are many ways

first by directly creating a table in the database using hook_schema and populate with hook_insert

second add field to existing content using hook_nodeapi and hook_insert

third by creating a custom content with cck ( hook_field_*) and populate with drupal_execute

I'm thinking to use the third way for reusability reason.

Hope somebody understand my problem and has an idea about it.

Thanks for any clue