Welcome to the forum Ipodd!
Enjoy your new ERA. I would suggest you wait to see if more power is needed, based on how you will use it, before spending much time and money on upgrades.
However, good batteries are a must, so test yours before a long trip to see if they retain a good charge. It's very possible that your batteries could have been abused or neglected as this is easy to do.
You probably have two AGM or two flooded batteries and a propane 3-way fridge. If you arrive at a destination with two good and fully charged batteries, they should be fine over-night and perhaps even a second day it you conserve. Do not plan on running your microwave or any heavy draw through your inverter using your batteries. Your appliances won't like it, and your batteries will hate it. Run your generator for a/c, microwave, etc.
We have taken pains to run down and eliminate unnecessary power drains. We have everything running on 12 volts, so we eliminate the need to run our inverter. Never turned in on in 3 trips totaling almost 6 weeks out.
We have the draw of a 12v-only compressor fridge but can still run, lights, tv/dvr, for 3-4 hours daily, ceiling fan (or furnace depending on the weather) overnight, and awake with 70-75% charge on on our batteries after 15 hrs. unplugged. We don't stay in one place more than a night unless we can plug in to 30amp service and we drive at least 5 hrs or more each day so we always start overnight with batteries that are fully charged.
If you plan to boondock without plugging in for several days, others can advise you better than me on what is best. In the meantime, get familiar with your rv by "camping" in your driveway overnight or make a short 1-2 night trip somewhere close by. Then, you'll have a better feel for how to manage in your van and what you need to pack along before your first long trip.