My list would be:

1. The Life, Walk and Triumph of Faith by William Romaine
2. Holiness by J C Ryle
3. The Mortification of Sin by John Owen or here.
4. The Poor Man's Morning & Evening Portions by Robert Hawker
5. The Lord's Prayer by Thomas Watson
6. The Ten Commandments by Thomas Watson
7. Body of Divinity by Thomas Watson
8. The Path of True Godliness by William Teellinck
9. We and Our Children by Professor Hanko
10. Spiritual Desertion by Gisbertus Voetius & Johannes Hoornbeeck
11. The Marks of God's Children by Jean Taffin
12. by Joseph Pipa

The above are all clear, simple and practical. Most are also very devotional.

__________________
Richard
CofE
UK