The proper gun builder and workbench takes time to develop... and it doesn't solve the issue of having to manually gear up every time you go out with the rest of your kit, but what if you could save a preset "bundle" of gear that would get automatically built from traders with a +5% cost of a builders fee?... You could unlock more as you level like 1 at level 10 then 2 at level 20 then 3 at 30, the preset would cover every single slot on your character including keys then just dump the rest back to inventory to sort later.
This way there is incentive to build from scratch if you want to experiment or save money with a budget kit, but if you're doing good and want to burn money you could use your presets.
This is also way easier to develop than a proper gun bench and synchronizes well with it once it finally comes, promoting preset "bundles" that might not have the weapon, which you would more manually build specifically and save a bit on the building fee.