The main problem is the awful connectors on the board. Wires poked into pin headers are brilliant for prototyping but awful for producing reliable installations.
If you take those connectors off and connect directly to the board you'll have something pretty damn robust IMHO. If you want to build you own you could start with something like this Diavolino . It allows you to choose your own power components, capacitors, etc.
With a decent power supply the difference between a slightly uprated Arduino and 'industrial' would mostly be down to the software.