My apologies if this has been addressed elsewhere in the thread - even if you do not get FPs for FoP, it's possible to do the ride at rope drop with a manageable wait. I was able to do this twice last week (in lieu of using two FPs I had for less convenient times later in those days).
On the first day, AK officially opened at 9 am. The gates opened at 8:15 and we were held at the entrance to Pandora until 8:30, as the CMs formed us into what would become the FoP line as we entered. The line never stopped moving and the ride was up and running well before 9 am (keep in mind anyone with FPs couldn't get through yet since the FP windows didn't start until the official opening at 9 am). Except for technical difficulties in the pre-ride area, I would've been off the ride before 9 am. My total wait time in line was around 30-35 minutes (which isn't too bad as I've read that FP waits can still run 20-40 minutes at times for this ride).
On the second day, I didn't arrive right as the gates or Pandora opened, but was in line by about 8:40. I was on the ride by 9:25. A little longer wait but a fair price for avoiding the claustrophobia of waiting with the crowds at the gate and entrance to Pandora. While I'd still suggest a FP if possible, I'm comfortable recommending RD strategy for this one.