For most cat owners, a tall cat tree is the better space-saving choice because it adds climbing height without drilling into walls or requiring a custom layout. Wall-mounted shelves win in very small homes when you can install them securely and design a safe route for your cat.
For most cats going on outdoor walks, a properly fitted cat harness and leash is safer than a backpack because it lets the cat move naturally while you maintain control. A backpack is the better choice for transport, busy areas, and cats that are not ready to walk outdoors.
For most healthy adult cats, Wellness CORE is the best grain-free brand to start with, especially its complete wet food recipes. Choose another brand when your cat has a clear preference for a certain texture, needs a veterinary diet, or you need a lower-cost option that still meets complete-and-balanced standards.