Thanks! Soldering is not optimal but it worked really well. It's a compromise between reliability and reconfigurablity.
Soldered edges are more rigid and more reliable. They're smaller, lighter and cheaper than most connectors and wires. So if you have a size/weight-constrained application (e.g., a drone) they do much better job. Of course, if you abuse them, you can pull the traces off but this is the case with any SMD connections. You can still use connectors instead. It does not change the main design concept.