The Sanibel is definitely pointed at the full timers. But I use the trailer so often (about 20-25 weekends a year plus a 2 week trip every winter) that it was perfect for me. The 3600 comes with a standard RV refer, 2 door stainless dometic, the 3601 has the residential refer unit BTW.
King size bed is standard on the 3600 as well as dual AC with ducted returns unlike the crusader that has dual AC option, but not the ducted returns. The storage in the 3600 is HUGE and flat compared to the Crusader, it comes with a larger gas/electric water heater (12g), and mine came with the level up system standard.
So it does come with more, but the question do you need/want more or is the crusader and 11k lower price better for how you use the trailer.