Speaking with the experience of living on stand alone for twenty-five years.
I was on a system that had 1.2kw nominal panels on trackers, with 24x2vx1100Ah deep cycle batteries, and two 2kVA (6kVA for five minutes) inverters. This proved 'adequate' for years, but I used the backup generator a lot, and battery life suffered.
Following a lightning strike a few years ago, this was replaced (under insurance) by 5.5kw nominal fixed panels (they are a lot cheaper than they were in 1994), same batteries and a single 7kVA inverter. The only time the backup generator has been started since was to check that it was wired in correctly. And my power use has increased - electric kettle, toaster, electric blankets, stopped worrying about power use as much.
The key is the amount of panels. Even under cloudy skies these provide significant power, meaning less load on the batteries, and fully charge the batteries with a much shorter period of sunlight than previously.
In my view, you do not have enough panels, but I would also think you need more battery capacity - discharging below 50% is a recipe for short battery life.
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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