boffin, Im a big fan of the deadbug style prototyping.
The hard part of building that circuit looks like the ribbon wire, that stuff isnt designed to be soldered, the insulation is designed for easy clean cutting with connectors. It shrinks way back when you heat the wire, you really need to pre-tin it, then trim the wire down after the insulation shops shrinking back.
Soldering LEDs without a board to hold them is a lot more difficult, and using some kind of jig to hold the parts while soldering really make a big difference in the end product.