Yeah I really like the size of the PJB stuff. Is there anything similar in size that sounds fuller?
No. Mr. Jones bent physics beyond what was thought possible when he made the D4 and nothing in the same size/weight ratio can keep up.
Bonus: The D4 runs off a laptop power bank, so your front porch does not even have to have an outlet.
If ease of transport is the main issue and you want to one-up the D4, the Barefaced one10 cabinet is a good contender,
that's a very loud 1x10" cabinet at 7kgs - add a class D head of your choice and you're well below 10kg, and it all fits neatly in a cajon bag.
Also, should money not really be an issue, the GR cabs are worth looking at.
I myself have a D4 and a Barefaced Super Mini. That's a 4kg combo amp and a 9.5kg cabinet. The latter can keep up with a loud drummer and is sufficient for more than 90% of what I do, including metal.
In a nutshell:
D4 is impossible to beat at the size/volume ratio of things. It's the smallest full sounding amp that can even do a low B with credible authority and it works in acoustic settings, but has to bow out once the drummer picks up the sticks.
GR makes incredibly light cabinets. A 112 is comparable to other 112 cabinets, but at a fraction of the weight. Careful: Carbon fiber sidewalls are incredibly stiff and make the cab work well as long as it's standing around, but they are not the sturdiest things against impact with pointy objects. Buy the padded cover if you intend to carry it around a lot.
Barefaced makes very light cabinets, but they are much louder than they have any right to be. Their 112 setups often successfully compete with 212 setups of quality brands.
Budget option:
Fender Rumble 100. A solid 112 setup at around 10kgs