"If I'm only going to 90% SOC when using the generator then the Noco can surely do that"
Yes, and so could a 3 amp charger. It is all about how long you want to run your generator. You have the timing information for various amp chargers, so just make your choice.
If you want to, go ahead and pay big bucks for a measly 26 amp charger--it's only money :)
An RV on solar is not the same as a stick house/cabin on solar. Different operating routines. "When in Rome---"
BTW, the 75ADJ pulls 1693VA from a Honda generator. (measured with a Kill-A-Watt) The Honda 2000 is rated at 1600VA but it does run the 75ADJ at sea level. Must be some wiggle room in the specs. However at altitude, it loses VA so at some altitude above sea level it won't run the 75ADJ anymore.
IMO you have all the information needed, but a conflicted set of priorities. It is up to you now. :)