Fishing bags are handled with wet hands, placed on rough surfaces and opened while the user is moving or balancing. A good specification begins with that behavior rather than a list of generic pockets.
Map what needs fast access
Separate frequently used tackle, tools, phone and personal items from the main load. Consider whether a front pouch, landing-net holder, rod attachment or transparent window improves use without creating new snag points.
Balance protection and access
Roll-top and airtight closures improve protection but can slow one-hand access. Magnetic lids and quick-access panels are useful when the product brief allows a different protection level.
Review the carry system under load
Check shoulder-strap position, handle balance, waist support and interference with life jackets or other gear. Test the bag loaded, not empty.
Plan for salt, sand and cleaning
Hardware, zipper pulls, coatings and welded seams should be reviewed for the intended environment. Smooth internal surfaces, drainage and removable components can make maintenance easier.