While testing our solar this year we used a single 95 ah grp 27 most of the time. We kept that up with a single 230w solar panel left portable so that it could track the sun if needed. It's cooler where we camp so we use the furnace nightly. Early spring/ late fall it can run day and night. We do have LEDs.
In our case 120w of solar would be on the slim side. I would suggest the 160w folding kit or possibly the 200w kit off of ebay for $300 and add hinges to make it portable.
The single battery was able to handle a cold cloudy day with lots of furnace use but a second would of had me looking for ways to recharge it so a second battery would give that buffer zone needed with solar.
We had a fella here with a Prowler last year and his battery tray sat under the propane door. In order to get two 6v batteries in there he had to trim the door a bit because they were too tall.
Now because my solar is not mounted and I'm not about to leave it out in the storage lot, I have to take my batteries home with me between trips for charging. This way we start each trip with a battery that's topped off as much as possible. Starting out with a low battery is putting you behind the 8 ball from the get go.
We never needed the generator for charging this year but last year we didn't have solar and used it daily for a few hours. That kept the single battery up day to day.
So my suggestion is a bit more solar, a extra battery and some inexpensive ebay LEDs.
