"It is all manual, so you do have to baby sit it "
When you are camping using the gen to recharge, you need to be there to turn it all on and off.  That is the extent of the baby-sitting with the gen and adjustable charger doing a 50-90.
You need to know when you are at 90 so you can turn off everything and put it all away till next time (in a few days, perhaps)  I use the Trimetric AH counter for that.
The only thing you need to do other than that is set the voltage to say 14.8 ahead of time.  After that you are free until you get to 90, which could be in two hours or so.  Walk the dog.  Read a book.  Whatever, it is not a big deal that will ruin your whole camping trip.
Here is the other end of the business, which you need to do anyway unless you have a built in Onan or whatever:
