I have the feeling that riveting put a lot of pressure on the plastic that could result into cracking after a while. Maybe adding a washer on the back could spread the load better.

Would screwing in the contacts not been easier?

I have designed and printed hundreds of parts on my 3d printer. My experience that if there too much tension on the material (especially with transparent abs) that it could grow cracks around the high pressure points. The print initially fine initally, but a week or so later it cracks.