Even I think of the P2 Elder in the same way. It wouldn't make sense to send a much higher ranking Pred to just oversee the P2 (and the others in the group, maybe) unless P2 belonged to the Royal family or something
Similarly, the AVP Elder too must not be having that high of a rank but I think he was higher than the P2 Elder just because of the fact that he had to overlook 3 of the 'trainees' and they were gonna encounter Xenos. But thats just me based on what I saw on-screen! :
Cheers,
Neo.
I personally feel the whole Lost clan was watching over P2. So maybe he IS part of the Royal family.
I always thought of the AVP Elder as some guy who goes around picking trainees up, dead or alive. The ship surely wasn't ALWAYS there when the AVP preds arrived on earth and began hunting, unlike P2 who probably arrived with the Lost ship, as he tried to escape in it.
So maybe he was the garbage man or taxi-ship driver that wasn't particularly high-ranking but has been doing it his whole life, earning enough respect that he could award whoever he damned well pleased.
Also while I'm at it, I do believe that P1 was a rogue hunter. I mean, everyone else was done after 1 hunt and got into a higher rank that ended their hunting career ala Lost Preds (P2, AVP, Predators). P1 seemed like he'd been around longer than all those, and should've been joining the Lost Preds lounging in the back of a ship waiting for another rookie to finish his hunt.
Just my opinions on these nerdy things.