Flashlights:

Everyone can use more flashlights, especially LED flashlights.

Parts Organizers:

If he seems to have everything, he probably needs more places to store all that stuff.

I think it's best if you can match the size and style he already owns, because too many mixed types can create more confusion and clutter.

Ebco folding sawhorses. Best given in pairs.

I added the piece of 2x4 myself. I have at least 6 pairs of these sawhorses, and I use them all the time.

Roller stands:

Best given in pairs.

Roller stands are very helpful for any handy person who owns a table saw, router table, or planer.

I have two pairs of roller stands, but I can see how a serious woodworker could use many pairs of roller stands.

Quick-Grip bar clamps come in many lengths and sizes. Very useful for home improvement and woodworking projects.

A serious handy person could find uses for a dozen of these.

Woodworker's clamps are somewhat useful, even for non-woodworkers.

I own a couple of these. I use them a couple of times a year, maybe.

Plain Old C-Clamps:

I don't know of any clamp that can exert as much squeezing force as a C-clamp. These are very useful for home improvement, woodworking, auto repairs, metal-working, welding, etc.