Benson does indeed have true jazz albums, quite of few of his early works were jazz and he was a session man on a lot of great recordings. He transitioned to a sort of jazzy pop-fusion but even then there are many jazz elements on his albums like Jorge Dalto's short but wonderful piano solo on "This Masquerade" to Phil Upchurch's wonderful bass work on In Flight. As time went on he moved pretty clearly into pop but he still has tons of jazz and jazz/pop albums in his catalog. I like
California Dreaming from his White Rabbit album but that whole album is quite good.
If you enjoy some Coltrane then
Giant Steps is classic and then on to
A Love Supreme.
I should have said, since you mentioned
Kind of Blue that it's difficult to go wrong with Bill Evans if you like more lyrical jazz. Bill Evans played piano on that album, he was also a session man for some important bands, and he had a prodigious if short solo career.
Sunday at the Village Vanguard is a great album, very intimately recorded but it could be that
Waltz for Debby, which I understand was recorded at the same event and released separately, might be even more enjoyable. The choice of songs on that album is superb aside from Milestones which seems very out of place to me and I feel clashed very badly with Bill Evans' style. The only thing that might bother some people about Bill Evans is that he played a fairly small catalog of standards, and so many albums have the same songs. He was a craftsman and an artist with a very delicate touch, and I believe he brought out the best in Miles Davis. When Bill and Miles played together, Miles' playing was at its pensive best, deep, penetrating, patiently saying what he wanted to say, with gorgeous clarity.
Oscar Peterson has some fantastic work and a huge catalog from a long career. He is certainly among the top jazz pianists of all time. The
Exclusively for My Friends series is a great place to start. The tracks are all enjoyable but my favorite of those albums is
Blackbird (Bye, Bye, Blackbird). This short but incredible rendition is an absolute textbook on stride piano that would make Fats Waller and Art Tatum jump for joy.
I love Monty Alexander's albums,
Love and Sunshine is at the top of my list of world's best piano albums. Jamento is very good and so are a lot of his other ones. Monty is unusual that he brings his Jamaican heritage into play and creates a unique style of jazz I haven't heard elsewhere.
Another favorite of mine is McCoy Tyner. He had a very long career (as far as I know he is still around) and put out some wonderful albums. His jazz is very workman-like, honest, and visceral.
SuperTrios is a good start. Some of his work is not so approachable but that album will give you an idea what McCoy Tyner has to say.
I also think Herbie Hancock's
Maiden Voyage is wonderful. Freddie Hubbard is absolutely mind-blowing on the title track, although he gets a little carried away at times. Herbie Hancock had a career similar to Miles in that he ranges from jazz to hard bop (to the extent that is possible on piano), some electronica (Sunlight), and some totally off the wall stuff which is hard to distinguish from noise, the sound of electric pianos bouncing down 50 flights of stairs or thrown off the top of an office building
Anyway, jazz is huge, it's classic American music that has extended its reach to the whole world and has many subcategories and variants. There is something for everyone