I personally think 4-1/8" is a tad long.
Moore Maker used to make a 3-7/8" trapper that was perfect; I have one in buffalo horn and one in yellow bone and they just nestle into my front pocket like they were born there.
The aforementioned copperhead is great, too, and the rounded ends really make it comfy.
I tend to carry only one knife at a time; if that won't do the job I'll open a toolbox.