It’s clear you are a big fan of Lithium batteries. And of course there are huge benefits to them.
But you keep repeating the benefits and ignore the drawbacks. Those are (still) price and complexity of the installation. Also I’m personally still not convinced about the claimed lifespan. If you see how much moderation on the batteries is taking place in electric cars by the charging/cooling/heating system, I have my doubts about batteries lasting 15 years in a much more hostile environment.
You also state the recharging process using solar as an alternative for the genset. That may be true on all the nice sunny days, but if you are having a few overcast days you are in trouble.
I’m not saying that Lithium is not a viable option, but there are more aspects to the installation then you like to highlight.