I think the strongest seasons of TNG are seasons 3 and 4 so just stopping after TBOBW wouldn't work for me.
Also, there are some gems on 5, 6 and 7.
I'll quote myself...
If you wish, you can create your own 3 season TNG by selecting all your favorites from seven season.
3 seasons x 26 episodes.
I tried this and this is what I came up with. 78 episodes. I count "Encounter at Farpoint" and "All Good Things" twice. It was a combination of episodes I rated 8 out of 10 or above and episodes that would be needed so there wouldn't be a significant loss of information.
1-2. Encounter at Farpoint
3. The Naked Now
4. Where No One Has Gone Before
5. The Battle
6. Datalore
7. 11001001
8. Coming of Age
9. Heart of Glory
10. The Arsenal of Freedom
11. Conspiracy
12. Elementary, Dear Data
13. The Measure of a Man
14. Time Squared
15. Q Who
16. The Emissary
17. Peak Performance
18. Evolution
19. The Ensigns of Command
20. The Survivors
21. Who Watches the Watchers
22. The Enemy
23. The Defector
24. Deja Q
25. Yesterday’s Enterprise
26. The Offspring
27. Sins of the Father
28. Allegiance
29. Hollow Pursuits
30. Sarek
31. The Best of Both Worlds, Part I
32. The Best of Both Worlds, Part II
33. Family
34. Brothers
35. Remember Me
36. Reunion
37. Future Imperfect
38. Final Mission
39. Data’s Day
40. The Wounded
41. Clues
42. Galaxy’s Child
43. The Drumhead
44. The Mind’s Eye
45. Redemption, Part I
46. Redemption, Part II
47. Darmok
48. Ensign Ro
49. Disaster
50. Conundrum
51. Power Play
52. Ethics
53. Cause and Effect
54. The First Duty
55. I, Borg
56. The Next Phase
57. The Inner Light
58. Schisms
59. A Fistful of Datas
60. Chain of Command, Part I
61. Chain of Command, Part II
62. Ship in a Bottle
63. Face of the Enemy
64. Tapestry
65. Lessons
66. The Chase
67. Frame of Mind
68. Rightful Heir
69. Second Chances
70. Timescape
71. Gambit, Part I
72. Gambit, Part II
73. Parallels
74. The Pegasus
75. Lower Decks
76. Preemptive Strike
77-78. All Good Things
For the heck of it, I'll do the same to TOS. To keep everything to scale: What if it only had three 13-episode seasons? Which would I choose? I left out "The Cage" because it's effectively a different show.
1. Where No Man Has Gone Before
2. The Enemy Within
3. The Naked Time
4. Balance of Terror
5. What Are Little Girls Made Of?
6. Conscience of the King
7. Galileo Seven
8. Court Martial
9. Shore Leave
10. The Squire of Gothos
11. Tomorrow Is Yesterday
12. A Taste of Armageddon
13. Space Seed
14. This Side of Paradise
15. Errand of Mercy
16. City on the Edge of Forever
17. Operation: Annihilate!
18. Amok Time
19. The Doomsday Machine
20. Mirror, Mirror
21. The Trouble With Tribbles
22. Journey to Babel
23. A Private Little War
24. Obsession
25. The Immunity Syndrome
26. A Piece of the Action
27. By Any Other Name
28. Return to Tomorrow
29. The Ultimate Computer
30. Assignment: Earth
31. The Paradise Syndrome
32. The Enterprise Incident
33. The Empath
34. The Tholian Web
35. For the World Is Hollow and I Have Touched the Sky
36. Day of the Dove
37. The Cloud Minders
38. Requiem for Methuselah
39. All Our Yesterdays