A pity indeed.
You know, you hear (of the Jungle Room sessions and others) how Elvis didn't even want to be there, that he just didn't care about recording at that time, that it meant nothing to him, etc.
Obviously he was reluctant to go into the studio in his final years, but once he got in there and the tape was rolling, what I hear is a dedicated performer putting all the emotion he could muster into his performances.
On the Jungle Room Sessions FTD Elvis sounds, if nothing else, like he cares plenty.
I can understand the songs he chose to sing at that time not being everyone's favorites, because they are on the whole a pretty somber collection of tunes, but if you look past that you see a lot of quality songs written by some great songwriters. I remember thinking when I got the CD (which preceded the Moody Blue upgrade, therefore I hadn't seen all those songs on one CD before), just looking at the titles, that it was such a strong collection.
Besides the caliber of the material, those often cheerless ballads represented where Elvis was at emotionally at the time. Had he been a songwriter, what he would have written during that period would probably have been along the same lines. So I don't think that his choice of material was uninispired or without purpose.
Personally, I don't find it depressing to listen to that type of material (like the Always On My Mind album). I find it a joy to listen to any type of music in which the singer is fully engaged and obviously feeling the music being performed. I am glad that Elvis performed the songs he did rather than ones which would not have seemed as natural to him at the time. We often lament the lack of rockers Elvis recorded during the 70's--understandable, being the king of rock and roll--but Elvis's story is very well told by his music, and if he had been singing songs besides those he could best relate to, that would not be the case.
Of course the few upbeat songs he did choose to sing during those sessions do come across very well, especially Moody Blue, in my opinion. But they were not what he was most into then, which we can deduce from their being such rarities.
So yes, Rick, I imagine most of us would love to have seen that session go on longer, or been continued some time in '77.