XF 60mm f/2.4 vs. XF 56mm f/1.2

As a portrait lens, there's no competition. You get the full-frame depth-of-field equivalence of an 85mm F1.8 lens with the 56mm while you get the DOF of a 90mm F3.6 lens with the 60mm. That's quite a difference in subject isolation and background blur, quite a difference. So for portraits, the 56mm lens complements the zoom you already own much better than the 60mm does. The 56mm also has potential for event shooting.

For close-up, semi-macro shooting, however, the 60mm complements your zoom much better than the 56mm does. So you need to decide which -- portrait or macro -- is your top priority.

I own both lenses but also own the 16-55mm zoom, which gives me F2.8 at 55mm -- fairly similar to the 60mm's F2.4. So I rarely use the 60mm anymore unless I'm doing close-up work -- flowers, copying photos, etc. If I'm doing head and shoulders or even half-torso shots, I carry the 56mm to supplement my F2.8 zoom. Sometimes I shoot it at F1.2 -- especially if the subject is farther away -- but more typically I shoot at F1.8 or 2.0 if the subject is closer.

Hope this is helpful. If I owned neither of them, I'd buy the 56mm. I've thought about selling the 60mm but keep it around for close-up shots. You might also consider the 90mm if a lot of your shooting is outdoors.

This website will do simulations of the depth of field for different lenses and apertures. You might find it useful.