There should be an option off the MFR options list to get R14 double insulation for roof and floor, plus an option for R38 extreme weather package, and if you call Forest River, they may give you a price for dual pane windows that your dealer may not know anything about. That happened with my recent purchase.
The addition of a 2nd A/C will likely boost the power supply needed on the camper from a 125V 30A to a 125/250V 50A, which can be very costly. But two A/C's are really the way to go if you can get it.
1994 Damon Hornet 27R
2008 Wildwood PT- 392FKTB (For Sale)
2016 Wildwood 4092BFL (Still Getting Fixed by Dealer After Production)