He was at different places when these albums were recorded, both mentally and spiritually, and that comes across in his composing and playing. Blue Train and A Love Supreme are apples and oranges, not just in sound, but in line up. Blue Train has 3 horns (Trane, Lee Morgan and Curtis Fuller) and that changes the dynamics and the relationship the rhythm section will have playing around them. A Love Supreme has Trane in his quartet, so he's the only horn. He has much more freedom, and is not constrained to share solos with other horns. The focus is on him solely, with his rhythm section playing around that.
Thematically, the mood and purpose of the albums will alter perceptions as well. I remember Gary Bartz saying that A Love Supreme is essentially a gospel album. He's right. Blue Train on the surface is a straight ahead, hard bop affair. However, it marks the beginning of Coltrane slowly shifting and implementing what is now known as Coltrane changes. He first did it on record on Blue Train. By the time A Love Supreme came around over 7 years later, he was a master of it and was a much more seasoned musician. Unless you understand the complexities of what Coltrane was doing, you're not really going to appreciate the growth in his playing from Blue Train to A Love Supreme.
Still, an easier listen and nice to kick back with on a cool fall evening!