The Simple The Next Generation Reading Lists are just my subjective versions of several condensed suggested reading lists, depending on the number of  books you might want to get.  Below are the top ten, twenty, thirty, forty, and fifty The Next Generation novels you should read.

CLICK HERE FOR THE FULL READING LIST.
Ten Series Era Novels

  1. The Buried Age
  2. Q-in-Law
  3. Federation
  4. Reunion
  5. Dark Mirror
  6. Vendetta
  7. Imzadi
  8. Q-Squared
  9. Intellivore
  10. Crossover

The Ten Essential Post-Nemesis Novels

  1. Destiny: Gods of Night
  2. Destiny: Mere Mortals
  3. Destiny: Lost Souls
  4. Cold Equations: The Persistence of Memory
  5. Cold Equations: Silent Weapons
  6. Cold Equations: The Body Electric
  7. Collateral Damage
  8. Coda: Moments Asunder
  9. Coda: The Ashes of Tomorrow
  10. Coda: Oblivion's Gate

Twenty Novel Version
(With Focus on the Series Era)

  1. The Buried Age
  2. Q-in-Law
  3. Federation
  4. Reunion
  5. Dark Mirror
  6. Vendetta
  7. Imzadi
  8. Q-Squared
  9. Intellivore
  10. Crossover
  11. Destiny: Gods of Night
  12. Destiny: Mere Mortals
  13. Destiny: Lost Souls
  14. Cold Equations: The Persistence of Memory
  15. Cold Equations: Silent Weapons
  16. Cold Equations: The Body Electric
  17. Collateral Damage
  18. Coda: Moments Asunder
  19. Coda: The Ashes of Tomorrow
  20. Coda: Oblivion's Gate

Twenty Novel Version
(With Focus on the Enterprise-E Era)

  1. The Sky's the Limit
  2. Slings and Arrows (ebook miniseries)
  3. Immortal Coil
  4. A Time to Kill
  5. A Time to Heal
  6. A Time for War, a Time for Peace
  7. Resistance
  8. Before Dishonor
  9. Greater Than the Sum
  10. Destiny: Gods of Night
  11. Destiny: Mere Mortals
  12. Destiny: Lost Souls
  13. Cold Equations: The Persistence of Memory
  14. Cold Equations: Silent Weapons
  15. Cold Equations: The Body Electric
  16. The Light Fantastic
  17. Collateral Damage
  18. Coda: Moments Asunder
  19. Coda: The Ashes of Tomorrow
  20. Coda: Oblivion's Gate

Thirty Novel Version
(With Focus on the Series Era)

  1. The Buried Age
  2. Q-in-Law
  3. Federation
  4. Reunion
  5. Dark Mirror
  6. Vendetta
  7. Imzadi
  8. Requiem
  9. Q-Squared
  10. Intellivore
  11. Crossover
  12. The Captain's Table: Dujonian's Hoard
  13. Triangle: Imzadi II
  14. The Sky's the Limit
  15. Slings and Arrows (ebook miniseries)
  16. Immortal Coil
  17. A Time to Kill
  18. A Time to Heal
  19. A Time for War, a Time for Peace
  20. Destiny: Gods of Night
  21. Destiny: Mere Mortals
  22. Destiny: Lost Souls
  23. Cold Equations: The Persistence of Memory
  24. Cold Equations: Silent Weapons
  25. Cold Equations: The Body Electric
  26. The Light Fantastic
  27. Collateral Damage
  28. Coda: Moments Asunder
  29. Coda: The Ashes of Tomorrow
  30. Coda: Oblivion's Gate

Thirty Novel Version
(With Focus on the Enterprise-E Era)

  1. The Sky's the Limit
  2. Slings and Arrows (ebook miniseries)
  3. Immortal Coil
  4. A Time to Kill
  5. A Time to Heal
  6. A Time for War, a Time for Peace
  7. Articles of the Federation
  8. Resistance
  9. Q&A
  10. Before Dishonor
  11. Greater Than the Sum
  12. Destiny: Gods of Night
  13. Destiny: Mere Mortals
  14. Destiny: Lost Souls
  15. Losing the Peace
  16. Typhon Pact: Paths of Disharmony
  17. Cold Equations: The Persistence of Memory
  18. Cold Equations: Silent Weapons
  19. Cold Equations: The Body Electric
  20. The Fall: Revelation and Dust
  21. The Fall: The Crimson Shadow
  22. The Fall: A Ceremony of Losses
  23. The Fall: The Poisoned Chalice
  24. The Fall: Peaceable Kingdoms
  25. The Light Fantastic
  26. Available Light
  27. Collateral Damage
  28. Coda: Moments Asunder
  29. Coda: The Ashes of Tomorrow
  30. Coda: Oblivion's Gate

Forty Novel Version
(With Focus on the Series Era)

  1. The Buried Age
  2. Survivors
  3. Metamorphosis
  4. A Call to Darkness
  5. Q-in-Law
  6. Federation
  7. Reunion
  8. Dark Mirror
  9. Vendetta
  10. Imzadi
  11. Requiem
  12. Q-Squared
  13. Intellivore
  14. Crossover
  15. The Captain's Table: Dujonian's Hoard
  16. Triangle: Imzadi II
  17. The Sky's the Limit
  18. Slings and Arrows (ebook miniseries)
  19. Immortal Coil
  20. A Time to Kill
  21. A Time to Heal
  22. A Time for War, a Time for Peace
  23. Death in Winter
  24. Resistance
  25. Q&A
  26. Before Dishonor
  27. Greater Than the Sum
  28. Destiny: Gods of Night
  29. Destiny: Mere Mortals
  30. Destiny: Lost Souls
  31. Losing the Peace
  32. Cold Equations: The Persistence of Memory
  33. Cold Equations: Silent Weapons
  34. Cold Equations: The Body Electric
  35. The Light Fantastic
  36. Available Light
  37. Collateral Damage
  38. Coda: Moments Asunder
  39. Coda: The Ashes of Tomorrow
  40. Coda: Oblivion's Gate

Forty Novel Version
(With Focus on the Enterprise-E Era)

  1. The Sky's the Limit
  2. Slings and Arrows (ebook miniseries)
  3. Section 31: Rogue
  4. Immortal Coil
  5. A Time to Be Born
  6. A Time to Die
  7. A Time to Sow
  8. A Time to Harvest
  9. A Time to Love
  10. A Time to Hate
  11. A Time to Kill
  12. A Time to Heal
  13. A Time for War, a Time for Peace
  14. Death in Winter
  15. Articles of the Federation
  16. Resistance
  17. Q&A
  18. Before Dishonor
  19. Greater Than the Sum
  20. Destiny: Gods of Night
  21. Destiny: Mere Mortals
  22. Destiny: Lost Souls
  23. Losing the Peace
  24. Typhon Pact: Paths of Disharmony
  25. Cold Equations: The Persistence of Memory
  26. Cold Equations: Silent Weapons
  27. Cold Equations: The Body Electric
  28. The Fall: Revelation and Dust
  29. The Fall: The Crimson Shadow
  30. The Fall: A Ceremony of Losses
  31. The Fall: The Poisoned Chalice
  32. The Fall: Peaceable Kingdoms
  33. The Light Fantastic
  34. Armageddon's Arrow
  35. Hearts and Minds
  36. Available Light
  37. Collateral Damage
  38. Coda: Moments Asunder
  39. Coda: The Ashes of Tomorrow
  40. Coda: Oblivion's Gate

Fifty Novel Version
(With Focus on the Series Era)

  1. The Valiant
  2. The Lost Era: Deny Thy Father
  3. The Buried Age
  4. Survivors
  5. Metamorphosis
  6. A Call to Darkness
  7. A Rock and a Hard Place
  8. Q-in-Law
  9. Federation
  10. Reunion
  11. Dark Mirror
  12. Vendetta
  13. Imzadi
  14. Requiem
  15. Q-Squared
  16. Intellivore
  17. Crossover
  18. The Captain's Table: Dujonian's Hoard
  19. Triangle: Imzadi II
  20. The Sky's the Limit
  21. Slings and Arrows (ebook miniseries)
  22. Section 31: Rogue
  23. Immortal Coil
  24. A Time to Kill
  25. A Time to Heal
  26. A Time for War, a Time for Peace
  27. Death in Winter
  28. Articles of the Federation
  29. Resistance
  30. Q&A
  31. Before Dishonor
  32. Greater Than the Sum
  33. Destiny: Gods of Night
  34. Destiny: Mere Mortals
  35. Destiny: Lost Souls
  36. Losing the Peace 
  37. Indistinguishable From Magic
  38. Cold Equations: The Persistence of Memory
  39. Cold Equations: Silent Weapons
  40. Cold Equations: The Body Electric
  41. The Light Fantastic
  42. Takedown
  43. Armageddon's Arrow
  44. Headlong Flight
  45. Hearts and Minds
  46. Available Light
  47. Collateral Damage
  48. Coda: Moments Asunder
  49. Coda: The Ashes of Tomorrow
  50. Coda: Oblivion's Gate

Fifty Novel Version
(With Focus on the Enterprise-E Era)

  1. The Sky's the Limit
  2. Slings and Arrows (ebook miniseries)
  3. Section 31: Rogue
  4. Immortal Coil
  5. A Time to Be Born
  6. A Time to Die
  7. A Time to Sow
  8. A Time to Harvest
  9. A Time to Love
  10. A Time to Hate
  11. A Time to Kill
  12. A Time to Heal
  13. A Time for War, a Time for Peace
  14. Death in Winter
  15. Articles of the Federation
  16. Resistance
  17. Q&A
  18. Before Dishonor
  19. Greater Than the Sum
  20. Destiny: Gods of Night
  21. Destiny: Mere Mortals
  22. Destiny: Lost Souls
  23. Losing the Peace
  24. Typhon Pact: Paths of Disharmony
  25. Typhon Pact: The Struggle Within
  26. Indistinguishable From Magic
  27. Typhon Pact: Plagues of Night
  28. Typhon Pact: Raise the Dawn
  29. Typhon Pact: Brinkmanship
  30. Cold Equations: The Persistence of Memory
  31. Cold Equations: Silent Weapons
  32. Cold Equations: The Body Electric
  33. The Fall: Revelation and Dust
  34. The Fall: The Crimson Shadow
  35. The Fall: A Ceremony of Losses
  36. The Fall: The Poisoned Chalice
  37. The Fall: Peaceable Kingdoms
  38. The Light Fantastic
  39. Takedown
  40. Armageddon's Arrow
  41. Prey: Hell's Heart
  42. Prey: The Jackal's Trick
  43. Prey: The Hall of Heroes
  44. Headlong Flight
  45. Hearts and Minds
  46. Available Light
  47. Collateral Damage
  48. Coda: Moments Asunder
  49. Coda: The Ashes of Tomorrow
  50. Coda: Oblivion's Gate