Hello James, wish I had come across this thread earlier to help you. How have you got on?
We come from a background of legacy diesel products, but import a range of hybrid generators from Italy and have done a lot of work on improving/developing these products, mainly to do with DSE controllers and Victron integration.
They are very simple and follow the same basic architecture regardless of size
DSE Controller
Victron Cerbo + GX Touch
Victron Quattro Inverters
MG BMS and Batteries
Victron MPPT Solar
The original version from factory used a DSE3110 basic controller often found on small rental generators or lighting towers. Very primitive but reliable.
This simply started and stopped the engine using the traditional dry contact/2 wire start function on the DSE.
You could obviously get all the telemetry in terms of power, remote start/stop - basically all the good things about VRM but there was a huge layer of invisibility from the generator side, and made any form of remote troubleshoot etc near impossible.
Things like fuel level in VRM would have required an additional tank sensor, you cant change the main buttons from stop>auto>start (huge flaw was customers manually starting generator in for example after it ran out of fuel, and not switching it back to auto) nor can you even see basic engine telemetry.
When victron went to 3.50 or 3.60 venus OS (cant remember which) we changed one unit to the DSE4520MKII with DSE855 ethernet adapter. Immediately fixed all of the above issues and unlocked a heap of visibility. Only con was it was a pain to integrate, no biggy just a hassle and labour time. Same applies to a DSE6120MKIII, no improvement but requires far more panel space.
We then recyled an older DSE7310 we had lying around, slightly easier but we now go to DSE7410/20 (you dont actually need the AMF function)
The DSE74xx series are way easier to integrate, from scratch (an absolute nightmare going from an existing DSE3110 to 7420) however if panel space is a premium I would go back to the 4520 with a DSE855. I hope this helps or maybe youve found an even easier way in the meantime, let me know!
The next evolution from here is looking into Comap and DEIF controllers talking direct to Cerbo GX (no GX touch required) and having everything all in one externally facing controller but still getting all the nice data on VRM.