Hi, I have a very similar idea, though I not yet have the time to make it. But now your mod is here, so maybe saving my effort! :-)
In my draft, I set such an item named as simple "Clothing" or "Builder's Suit" or "Power Suit" (not finalized yet). Have upgrades like Power armors. They will give no (or very little) resistance bonus, but have quite large inventory size bonus.
Also have equipment grids, even larger size than power armor of the same tier but can only put in non-military equipment (excluding personal laser defense, energy shield).
This needs a bit more work, though not too hard. Just add an extra "equipment-category" type with name "clothing" (or whatever you like). Then add an extra "equipment-grid" type where equipment_categories = {"clothing"}. Then set every non-military "equipment" type with categories appended with "clothing".
Could you add these? Or feel it's too complicated or not needed in your mod?
I'm okay even if you reject these suggestions. Just let me know your decision. ;-)
