PDF workflows become much easier when the job is clear first. Combining files, cutting pages, shrinking size, and extracting content are separate document tasks with different tradeoffs.
The best preparation flow usually matches the next destination, whether that is an upload form, client packet, archive, or content-extraction step.
Use Merge and Split Tools for Structure Problems
If the document problem is too many files or too many pages, start with merge or split tools before changing quality settings.
Use Compression Only When File Size Is the Constraint
Compression is strongest when the PDF structure is already right and the real blocker is attachment size or upload limits.
Use Conversion and Extraction for Reuse
If the goal is to reuse content in another format, converters and text extractors are usually more useful than structural PDF tools.