The fine motor control that comes of handwriting is critical if he likes to tinker or discovers any sort of work/hobby that requires manual dexterity.
Keep pushing on that, also, get a book on how to print like you're writing the dialogue in a comic book or how to print like an architect making a blueprint. If he can work out the shapes and spacing, he can develop his own legible style in time and move on to a fusion-style cursive with those print shapes.. It realy does make a difference in note-taking.
My dad was a design draftsman and taught me how to do that block print that I'd see on blueprints, and I have a super easy to read cursive based on that now.