All just my personal opinion
Domenico Scarlatti: Keyboard Sonatas — recordings with Pieter-Jan Belder and Andreas Staier; Schubert: Masses in A♭ (D.678) and E♭ (D.950) — Nikolaus Harnoncourt, Chamber Orchestra of Europe, Arnold Schoenberg Choir
Bach: Cantata BWV 140, “Wachet auf, ruft uns die Stimme” — Comparing 5 recordings: Leppard/English Chamber Orchestra, London Voices (1981), Harnoncourt/Concentus musicus (1984, partial), Gardiner/Monteverdi Choir/English Baroque Soloists (1992), Koopman/Amsterdam Baroque Orchestra & Choir (2006), Lutz/J.S.Bach-Stiftung St.Gallen (2008, DVD)
Beethoven: 6 Bagatelles, op.126 — Ashkenazy (1984), Brautigam (2010), Brendel (1964 & 1985), Gould (1974), Schnabel (1937); Beethoven: 24 Variations on the Arietta “Venni Amore” by Vincenzo Righini, WoO 65 — Pletnev (1997), Brautigam (2012); Schubert: Symphony in B minor, D.759 (“Unfinished”) / Symphony in C major, D.944 (“Great C major”) — Furtwängler (1952), Harnoncourt (1992), Dausgaard (2006)