you are producing 16a. (this is 200watts from your 500w solar) maybe for 5 hours / day this time of year? so that is 80ah per day you are making.
when you wake up at 12.1v your battery bank is at 50% so you are down 235ah
so if you turn everything off it would take 3 days to get them charged. ( 3x80ah to get the 235 back)
but durring the day you are probably using 100ah+
so you wake up with 50% batteries. put 80 in and take 100 out and when you go to bed
you are still at 50% batteries. slowy draining and never charging. you are just slowing the drain.
what you need is a battery monitor
like a victron 712 to watch your battery usage
you probably need to run the gen in the morning for a couple hours each day. though with the 30a charger
you are wasting your time. get your self an 60-80a charger. then maybe you can run for 1 hour a day instead of 3 hours a day.
upgrading or changing the bank does not solve this issue. you are using more then you are charging.
I would also look at why the 500w solar is making 200w. but that is likly normal for winter
. since both pairs are equal.