I think 3600 watts would be plenty for almost all uses, unless you did have the 200 amp charger, low batteries, and were running the microwave or something else that used big
Not likely to happen, I would think.
I think most of the good chargers can be paralleled , so you might need to do that to get the higher charge rates. I really don't know anything about really high rate battery charging, so maybe 100 or 150 amps would be plenty and better for the batteries.
I think that Sterling makes a 200 amp remote regulator that claims multistage charging, with variable timing, which might also be a possibility, if you didn't want to go to big charger off the inverter. If it got to float easily, or manually, you wouldn't need the disconnect on it.
So another system could be 200 amp alternator with 3 step regulator, 3600 watt inverter, 100 amp charger, 400-600AH of AGMs, and 300-600 watts of solar? All run off the second alternator.