Never heard the Last Album, but the other two in question from this period, New Grass and Healing Force, Healing Force, IMO is a far better, and more cohesive work. I actually dig Ayler's bagpipe chantor (or whatever its called) in a free jazz context and the double basses add a richer context to the music. Now having said that, the first three tracks are really good and recall the more experimental period up to about 1967, then the next two tracks are more of a throwback to New Grass. Drudgery, the final track, is somewhere in between, a peculier track at best. New Grass, on the other hand, which is an album that has its moments, just never really warmed up to me. I think I understand that Ayler had a "new message" but I guess I just don't like the context, which that message was given in. Oh well.
I prefer from his Impulse! period, The Complete Greenwich Village and Love Cry instead.