So it isn't decisively settled? Rats! Of course, I just looked through a couple hundred pictures of He-111s (primarily online) and I've yet to see a load-out that matches the original one in Il-2 - although I've found pictures of He-111's carrying a single 250kg bomb externally (which means that we're missing the 250kg payloads)!
There were PVC1006 were designed for large bombs, but were converted for torpedoes (PVR1006L?) - in addition to the ETC-2000.
The five bomb universal rack is refered to as another form of PVC and was introduced on some H-11 series (according to the Wikipedia - however I lack the book cited).
Here is a picture showing the same rack with what appear to be the small supply pallets (there were at least three types - 250kg ones, 700kg crates, and the late war 800kg ones).
P.S. Bizarrely, there is also mention of a field mod with three fixed forward firing guns!