The One Thing Needful by Archbishop Andrei is a collection that represents the very under-represented Orthodox tradition.
Lenten Sermons Preached in Oxford (8 vols.) by Samuel Wilberforce. Yes we have lots of Anglican material but generally by a single author. This fills in with less known names.
The D.A. Carson Sermon Archive has over 500 sermons (with audio) by this perennial March Madness winner. Would love to see this get some TLC too.
