Diary, an album by Ralph Towner of Oregon from 1973 features him on both piano and guitars(12 string and classical) and is highly recommended for your purposes. I also can second the recommendations for fellow ECM artists:
Ketil Bjornstad "The River" and "The Sea".
Peter Erskine" Time Being", "As It Is", "You Never Know" in trio format with John Taylor on piano.
BoBo Stenson "Serenity".
Vassilis Tsabropoulos "Achirana" Trio format. All the above are in an introspective contemporary style.
Also consider most of the classic Bill Evans albums from the early 60s.
Ketil Bjornstad "The River" and "The Sea".
Peter Erskine" Time Being", "As It Is", "You Never Know" in trio format with John Taylor on piano.
BoBo Stenson "Serenity".
Vassilis Tsabropoulos "Achirana" Trio format. All the above are in an introspective contemporary style.
Also consider most of the classic Bill Evans albums from the early 60s.