By the way, the other thing I learned in that first year was that it's a very bad idea to leave the house plugged in all the time while in storage. That dumb Parallax converter the PC came with cooked $300 worth of house batteries. After replacing the house batteries with AGM's, I replaced the Parallax with a smart converter (Progressive Dynamics PD9245CV Inteli-Power 9200). But I still don't leave it plugged in all the time.
You can leave the house batteries plugged in if AGM and using a smart charger. (I have done it for years) If you have standard lead-acid batteries you would need to keep an eye on the water level.
I was really surprised that the Parallax was still the standard charger being used by Phoenix when I ordered my 2017. As you mention, it can easily burn up your batteries. A smart Progressive Dynamics is not much more. I had them switch to the PD charger for my build.