That looks great!
The buggy type setup with the extra wheel for the front looks quite convenient. One downside of the purpose-built cargo trailer is that it lacks any good way to detach it for wheeling around in shops, so I end up using it more like a vehicle trunk/boot and unloading everything from the shopping cart back onto the bike. There are shopper type cargo trailers available, but they generally look awkward and do not have a very high weight rating.
The stroller bar may create some other interesting possibilities for securing bulky or fragile items as well.