Agree on pegboard. Unless you are hanging odd-shaped tools, in an area that can't be used for shelving, shelving of some type (wire or wood) is typically a better choice IMO. The depth adds space that would otherwise be wasted. Doesn't even have to be deep to gain much useable space.

Also depends where your lighting will be. Shelving over a workbench could block light.

I will be building a workbench, my dad suggested attaching a 2x4 to the studs lengthwise along the wall, using that to anchor the back side of the table top. I'll be using 4x4's for the front legs (three, due to the width of the work bench) and I happen to have two larger chunks of 3/4" MDF (heavy!) that likely will be used for the top of the bench. At his suggestion I may get a fairly thick sheet of steel for the top. If I use steel, it will be something thick enough that I won't be able to dent it, or easily drill through, or grind, etc. That way I can count on it being a flat surface for a long time.

I plan on running a 2xsomething lip along the back edge, so nothing can roll off the back of the table to resist finding.

IMO weight is a plus for a bench. That way mounting a vise, drill press, grinder, or anything else that you may put leverage on, or need stability for precision, won't move around while you are working. For model stuff the leverage issue may not be as critical, but when working on automotive stuff, many times having a solid mounted vise makes work MUCH easier. On the hobby side, if you are working on something very small, and bump the bench, it would be nice for the work piece not to move.