Shooting a heavy bow will take some time, but it can be accomplished with dedication and work. Just go slowly and be patient. Anyone can learn to pull a heavy bow, but the issue often comes with developing good form. Form should always trump poundage.
As for vanes, I have never had a bow that shot them well off the shelf. (This was way back in the 1980's, so it is possible that plastic vanes are made with better characteristics now.) I have tried it on bows from 40 # to 78#. None of my bows had elevated rests, though. To me, they just aren't worth the effort. I have never tried it using an elevated rest.