Suspension is one of the biggest upgrade paths for the Colorado. The Dirt King Boxed Upper Control Arms are a solid starting point for improving the front end, while the FOX Factory Race Series 2.5 Coilovers take things considerably further for off-road use.
Powertrain upgrades can be as simple as changing airflow or throttle response. The Injen PowerFlow Intake is available for 2017-2022 3.6L trucks, while the Pedal Commander Bluetooth Throttle Controller is another option for changing how the truck responds to pedal input.
Exterior upgrades can make the Colorado more useful without changing what makes it a good midsize truck. Something like the BAKFlip MX4 for the 5-foot Colorado/Canyon bed gives you covered bed storage while keeping the truck practical for daily use.
Better lighting makes a lot of sense once the Colorado starts seeing dirt after dark. The Vision X CR-Series Fog Light Upgrade Kit gives 2015-2021 Colorado and Canyon owners a vehicle-specific, plug-and-play fog light upgrade.
For camping and longer trips, storage usually becomes more important than adding parts just for appearance. The OVS 53QT Aluminum Storage Box is a simple way to keep tools, recovery equipment or camp gear organized in the truck.
If the Colorado regularly leaves pavement, recovery gear should be part of the build early. MAXTRAX Xtreme Recovery Boards and the ARB Premium Recovery Kit are good places to start before you actually find yourself stuck.
Wheel width, offset, tire size and suspension all need to work together on a Colorado. The Method 701 is a good example of the kind of off-road-focused wheel that works well when you're building around more tire sidewall and actual trail use.
Once you're adding lights and other electrical accessories, a clean way to control everything becomes important. The Switch Pros RCR-FORCE-12 gives you one place to manage a larger accessory setup from inside the truck.