Congrats! We also have a NT 32, but ours is the East Coast version with the genny and two AC units. That said, we don't really use the AC much when we anchor out (thus not much use on the genny) so I can give you some guidance. We have a house bank consisting of four 6 volt golf batteries, so somewhere around 420 AMP hours. We have converted all the interior lights to LED, so there isn't much draw there (before converting we found the halogens using more amps than the fridge). We do not have an inverter, and we have a propane stove. We can easily go two days without using the generator or running the engine before the batteries get down to 50% (we actually never let them get that low). The biggest draw is the fridge at around 4-5 amps, and the anchor light at 1-2 amps (changing to led this winter). Head and water usage isn't really much of a factor. I second the recomendation to get an amp/state of charge meter. It will help you determine your amp usage and, more importantly, will help prevent you from running down the batteries too much. Getting back to the generator, we do use it in the morning to heat the hot water, make coffee, and run the microwave if we need to. Coffee is a non-negotiable item on our boat. This is more than enough usage to keep the batts topped up, but as I said, not necessary if you move the boat every day or two. With your setup, and depending on your battery bank, an inverter that could run a coffee maker and microwave, coupled with a couple solar panels, would probably be about perfect.
I also suggest you join the SENTOA owners forum. Lots of owners with plenty of NT specific experience to share, and many in your cruising area.