The tackle box takes the same kind of memory space as a regular inventory, and it's also loaded along with everything else every time you zone somewhere or enter a duty. Instead of adding a tackle box they gave us more inventory slots since they use the same resources, and gave us a saddlebag for the extra stuff you immediately need. Make use of what you were given.

The only QoL change I'd request is for fisher to directly access the baits and tackles stored in the saddlebag.