I read somewhere over the rainbow that is not that Elvis didnt liked Burning Love, but that he liked sometimes sometimes not, I mean, it was like sometimes he was on the mood to doit, sometimes not, best Elvis Live version of that song for me is the one on Memphis '75; what do you think of the alternate version with the Wha wha pedal at the begining isnt it soo cool, I would love to heard it played tha way on the Madison Square Garden '72 gigs.
About more hard rock songs, I read somewhere that he indeed wanted to be a rock and roller again between '72 -'73 but it was the usual fear, just as in '74 we he changed his song selection to the usual one after changing his wholw repertory for his live show cause people wanted to see his doing the same old songs, and the true is that the mayor part of his fans are more into the big ballads, not as much with his R&B, Hard Rock and Blues material, which personaly is what I love the most. (Not that I dont like the balads, but I woudl have love to see him doing a pure rock show during the 70?s)
About working whith other Artist, I guess Elvis was aware that he only have to move his little finger to have people as big as Lennon/Mcartney or Bob Dylan to be working with him, but the Coloner would have never let him doing something like that, remeber how the Coronel blackmailed Leiber/Stoller to get them away from Elvis when Elvis was considering them as his mayor songwriting team? or remeber when during the early '70 Elvis wanted so bad to do something with James Brown, but once again... I mean I cant belive that Elvis did never toured overseas, no matter what explanaition you give, its ridiculous that the biggest entretainer fo the XX century never playied a concert outside the States.
Just imagine a european tour back in '58, that would have been bigger than the Beatles in the states in '64; or a world wide tour in '73 after the Aloha... just imagine.