Another final design which ended up an incremental improvement.  It collapses the smallest of any of them.  It would collapse further if the hinge was right on the bottom, but this would interfere with the bits needed to stabilize the legs.

 It's rigid despite using panel legs.

It stands on its end.  This requires unbolting the light.  The washer spreader really needs knurls.

Another way to stand on its end while disassembled is less stable.

Tongue & latch design attaches the panels at right angles without tools.

Switch is a real pain to install, even with the tool.  It might be smarter to stick it out the side.  It's not ideal to have the battery cable going down the handle instead of sideways. It might actually be best to go up & over the side.  These are really minor details.

The switch tool gets just enough grip to tighten the nut but isn't as easy to use as hoped

Disappointing to have all the locking mechanisms exposed on the bottom & prone to getting knocked loose.  As usual, the ugliest panel design is the most practical.

Maybe the battery tray could carry other junk.

Comparison with other light sources.