it is hard to pick any (some) particulas favourite, obviously. GT lesson library is so comprehensive.

Here are some of my favourites

Ben Lindholm's "10 Ways To Play Arpeggios" https://www.guitartricks.com/tutorial.php?input=1310

Christopher Schlegel's "Connecting Pentatonic Patterns: Series 2" https://www.guitartricks.com/tutorial.php?input=843

From song lessons I pick

Christopher Schlegel's "Summertime (Jazz)" lesson for easy to approach chord melody playing https://www.guitartricks.com/tutorial.php?input=2189

Michael Elsner's "Pull Me Under" lesson. I'm not so much into song itself, but many of lesson parts serve as great playing technic excersises https://www.guitartricks.com/tutorial.php?input=1290

And I can't left to mention all of Christopher Schlegel's music theory related lessons.

A lot of great stuff in GT.