We went through the same problem, the 2kW inverter died (it is actually not a 2,5 kW inverter, the continuous load is only 2kW). So we also replaced the thing with the Mass Combi Ultra.
Although it did take it a step further. I have also installed a full Masterbus network and a Mastervolt Easy Display that you can configure to have a button to switch on/off the inverter remotely. It also connects to the two existing chargers, the alternator controller, the Mastershunt and solar controller.
Next I removed the switchover logic from Amel in the engine room in the grey box next to the generator and installed a 230V/32A relay with a 24V coil. I change the setup in the 230V breaker panel a bit as well.
The switchover for the generator is embedded in the Mass Combi together with the switchover for the inverter as pointed out by Nick.
The result is I now have a fully transparent switchover between sources without the 230V appliances even noting it.
Another thing I now am capable of is converting the 60Hz shore power we have here in Saint Martin to 50Hz using the Mass Combi and the Mastervolt Chargemaster 100A simultaneously, one to do the inverting and one to keep the batteries topped up. This is where the new relay comes into play.
If you like I have drawn a new schematic on how the system is laid out.
I did not have to route new cables apart from some short pieces, I did have to change/relocate the circuit-breaker that was in the feed-line of the inverter (from 100A to 200A). I checked the cable between the breaker and the inverter and it was thick enough for the 175A that it can use, so was the cable between the breaker and the batteries. That saved a lot of effort.