You forgot
Books of Magic! Sooooooo good. Kinda like a twisted Harry Potter? Hahaha. I think this came before Harry Potter. Well, the main character at least looks similar. I think for an LOTR lover who likes graphic novels this may be a solid bet!
The only thing with Books of Magic is that they aren't available as a compilation (at least last I checked) and it's really confusing what their original order was. I think I grabbed a random book and thought it was book 1 but it may have been way into the middle of the storyline for all I know. The beauty of the series though is that I still got and enjoyed a lot of the story.
Or the Hugo and Nebula winner compilation for this year? He probably already read them if he's a sci-fi fan.
Not from an INTP, but I know I really enjoyed Books of Magic.
Good luck!
(And isn't it nice having a sweetie to shop for??)