Solar panels and lithium batteries

I think your first step should be to conduct an energy audit to determine your needs. It is understood that you have already replaced anything you can with low wattage equivalents (like led lights). You need to be able to measure your actual energy flows. A simple current monitor on the battery bank can be added at little cost that will give you lots of useful information. Once you know what is going on you can made an informed decision as to the equipment needed to meet your goals.