Well I took a look at it. I'm not just sure about the best way to go about it at this time.
The Mouse/Keyboard/Display and Cursor classes with static methods in LWJGL are gone since changing to glfw. Instead you register callback functions.
These callback functions receive a window pointer so you can control multiple windows. I guess one easy way to to get TWL to work with glfw would be to reimplement Mouse and Keyboard have them grab the callbacks and only support one window.
GLFW is certainly a big improvement over what was used in LWJGL 2. Nice API with enough documentation. Great support for multiple monitors and much more.http://www.glfw.org/docs/latest/modules.html
Cursor handling is much better you can set a cursor to be in Normal, Hidden and Disabled mode. Disabled meaning it is hidden and locked and when you drag you get unlimited x and y coordinates, perfect for free look. Hidden moves the invisible cursor just giving coordinates within the limits of the window or screen resolution in case of fullscreen. I found the grabbed solution in lwjgl 2 always needing some hacky solution with Robot for free look.
One thing lacking LWJGL 3 is a usable GUI library. I like TWL since you can do pretty much anything with it
. With the theme editor as a nice reference implementation of a real application.
I'll let you know if I get somewhere with TWL and GLFW.